// ===========================================================================
// This file has been generated by
// Rats! Parser Generator, version 1.14.3,
// (C) 2004-2009 Robert Grimm,
// on Sunday, September 20, 2009 at 10:45:26 AM.
// Edit at your own risk.
// ===========================================================================

package xtc.lang.c4;

import java.io.Reader;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.OutputStreamWriter;
import java.io.IOException;

import java.util.HashSet;
import java.util.Set;

import xtc.util.Action;
import xtc.util.Pair;

import xtc.tree.Node;
import xtc.tree.GNode;
import xtc.tree.Printer;

import xtc.parser.ParserBase;
import xtc.parser.Column;
import xtc.parser.Result;
import xtc.parser.SemanticValue;
import xtc.parser.ParseError;

/**
 * Packrat parser for grammar <code>xtc.lang.c4.C4</code>.
 *
 * <p />This class has been generated by the <i>Rats!</i> parser
 * generator, version 1.14.3, (C) 2004-2009 Robert Grimm.
 */
public final class C4Parser extends ParserBase {

  /** The GCC flag. */
  public static final boolean GCC = true;

  /** The C_KEYWORDS set. */
  public static final Set<String> C_KEYWORDS = new HashSet<String>();

  /** The RELOCATE flag. */
  public static final boolean RELOCATE = true;

  /** The ASPECT flag. */
  public static final boolean ASPECT = true;

  /** The C99 flag. */
  public static final boolean C99 = true;

  // =========================================================================

  /** Chunk 1 of memoized results. */
  static final class Chunk1 {
    Result fFunctionDefinition;
    Result fDeclarationList;
    Result fDeclarationList$$Plus1;
    Result fDeclarationSpecifiers;
    Result fSpecifierQualifierList;
    Result fOptionalStructureDeclaratorList;
    Result fAttributedDeclarator;
    Result fDeclarator;
    Result fPointer;
    Result fVariableLength;
  }

  /** Chunk 2 of memoized results. */
  static final class Chunk2 {
    Result fParameterTypeList;
    Result fAbstractDeclarator;
    Result fTypeName;
    Result fAttributeSpecifierList;
    Result fAttributeSpecifier;
    Result fStatement;
    Result fCompoundStatement;
    Result fLocalLabelDeclaration;
    Result fLocalLabelDeclaration$$Star1;
    Result fDeclarationOrStatement;
  }

  /** Chunk 3 of memoized results. */
  static final class Chunk3 {
    Result fCommaExpression;
    Result fAssignmentExpression;
    Result fConditionalExpression;
    Result fLogicalOrExpression;
    Result fCastExpression;
    Result fUnaryExpression;
    Result fExpressionList;
    Result fExpressionList$$Star1;
    Result fSimpleAssemblyExpression;
    Result fAssemblyOperands;
  }

  /** Chunk 4 of memoized results. */
  static final class Chunk4 {
    Result fAssemblyOperands$$Star1;
    Result fAssemblyOperand;
    Result fAsmKeyword;
    Result fExponent;
    Result f$$Shared2;
    Result fBinaryExponent;
    Result fCharacterLiteral;
    Result fStringConstant;
    Result fStringConstant$$Plus1;
    Result fStringLiteral;
  }

  /** Chunk 5 of memoized results. */
  static final class Chunk5 {
    Result fIdentifier;
    Result fKeyword;
    Result fWord;
    Result fSymbol;
  }

  // =========================================================================

  /** Memoization table column. */
  static final class C4ParserColumn extends Column {
    Chunk1 chunk1;
    Chunk2 chunk2;
    Chunk3 chunk3;
    Chunk4 chunk4;
    Chunk5 chunk5;
  }

  // =========================================================================

  /** The global state object. */
  protected final C4ParserState yyState;

  // =========================================================================

  /**
   * Create a new packrat parser.
   *
   * @param reader The reader.
   * @param file The file name.
   */
  public C4Parser(final Reader reader, final String file) {
    super(reader, file);
    yyState = new C4ParserState();
  }

  /**
   * Create a new packrat parser.
   *
   * @param reader The file reader.
   * @param file The file name.
   * @param size The file size.
   */
  public C4Parser(final Reader reader, final String file, final int size) {
    super(reader, file, size);
    yyState = new C4ParserState();
  }

  // =========================================================================

  protected Column newColumn() {
    return new C4ParserColumn();
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.TranslationUnit.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  public Result pTranslationUnit(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Unit>.

    yyResult = pPrelude(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pExternalDeclaration(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Node v$el$1 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$g$1.
        final Pair<Node> v$g$1 = yyRepValue1.reverse();

        yyResult = pAnnotations(yyRepetition1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$2 = yyResult.semanticValue();

          yyResult = pEndOfFile(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {

            yyValue = GNode.create("TranslationUnit", v$g$1.size() + 1).
              addAll(v$g$1).add(v$g$2);
            yyValue.setLocation(location(yyStart));

            return yyResult.createValue(yyValue, yyError);
          }
        }
      } // End scope for v$g$1.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Prelude.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  public Result pPrelude(final int yyStart) throws IOException {
    Result     yyResult;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Reset the global state object.
    yyState.reset(column(yyStart).file);

    // Alternative 1.

    yyResult = pDirective(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyValue = null;

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ExternalDeclaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  public Result pExternalDeclaration(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative <Declaration>.

    yyState.mark();

    yyResult = pDeclaration(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node d = yyResult.semanticValue();

      yyValue = yyState.annotate(d);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <GlobalAdvice>.

    yyResult = pGlobalIntroductionAdvice(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node ga = yyResult.semanticValue();

      yyValue = yyState.annotate(ga);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Function>.

    yyResult = pFunctionDefinition(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node fd = yyResult.semanticValue();

      yyValue = yyState.annotate(fd);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <AspectFunction>.

    yyResult = pAspectFunctionDefinition(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      // Commit the state modification.
      yyState.commit();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Assembly>.

    yyResult = pAssemblyDefinition(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node a = yyResult.semanticValue();

      yyValue = yyState.annotate(a);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Empty>.

    yyResult = pEmptyDefinition(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node e = yyResult.semanticValue();

      yyValue = yyState.annotate(e);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.FunctionDefinition.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pFunctionDefinition(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fFunctionDefinition) 
      yyColumn.chunk1.fFunctionDefinition = pFunctionDefinition$1(yyStart);
    return yyColumn.chunk1.fFunctionDefinition;
  }

  /** Actually parse xtc.lang.c4.C4.FunctionDefinition. */
  private Result pFunctionDefinition$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Object     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Definition>.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyBase   = yyOption1;
    yyResult = pKeyword(yyBase);
    if (yyResult.hasValue("__extension__")) {
      final String v$el$1 = "__extension__";

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    } else {
      yyError = yyError.select("'__extension__' expected", yyBase);
    }
    { // Start scope for v$g$1.
      final String v$g$1 = cast(yyOpValue1);

      yyOpValue1 = null;

      yyResult = pDeclarationSpecifiers(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$2;
      }
      { // Start scope for v$g$2.
        final Node v$g$2 = cast(yyOpValue1);

        yyResult = pDeclarator(yyOption1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$3 = yyResult.semanticValue();

          yyResult = pFunctionDeclaratorContext(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {

            yyOption1  = yyResult.index;
            yyOpValue1 = null;

            yyResult = pDeclarationList(yyOption1);
            yyError  = yyResult.select(yyError, yyOption1);
            if (yyResult.hasValue()) {
              final Node v$el$3 = yyResult.semanticValue();

              yyOption1  = yyResult.index;
              yyOpValue1 = v$el$3;
            }
            { // Start scope for v$g$4.
              final Node v$g$4 = cast(yyOpValue1);

              yyResult = pCompoundStatement(yyOption1);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {
                final Node v$g$5 = yyResult.semanticValue();

                yyValue = GNode.create("FunctionDefinition", v$g$1, v$g$2, v$g$3, v$g$4, v$g$5);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              }
            } // End scope for v$g$4.
          }
        }
      } // End scope for v$g$2.
    } // End scope for v$g$1.

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DeclarationList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationList(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fDeclarationList) 
      yyColumn.chunk1.fDeclarationList = pDeclarationList$1(yyStart);
    return yyColumn.chunk1.fDeclarationList;
  }

  /** Actually parse xtc.lang.c4.C4.DeclarationList. */
  private Result pDeclarationList$1(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <List>.

    yyResult = pDeclarationList$$Plus1(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Pair<Node> v$g$1 = yyResult.semanticValue();

      yyValue = GNode.createFromPair("DeclarationList", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.DeclarationList$$Plus1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationList$$Plus1(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fDeclarationList$$Plus1) 
      yyColumn.chunk1.fDeclarationList$$Plus1 = pDeclarationList$$Plus1$1(yyStart);
    return yyColumn.chunk1.fDeclarationList$$Plus1;
  }

  /** Actually parse xtc.lang.c4.C4.DeclarationList$$Plus1. */
  private Result pDeclarationList$$Plus1$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Pair<Node> yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pDeclarationListEntry(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$el$1 = yyResult.semanticValue();

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyResult = pDeclarationList$$Plus1(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Pair<Node> v$2 = yyResult.semanticValue();

        yyValue = new Pair<Node>(v$el$1, v$2);

        return yyResult.createValue(yyValue, yyError);
      }

      // Nested alternative 2.

      yyValue = new Pair<Node>(v$el$1);

      return new SemanticValue(yyValue, yyChoice1, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DeclarationListEntry.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationListEntry(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative <Entry>.

    yyResult = pDeclaration(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      // Commit the state modification.
      yyState.commit();

      return yyResult.createValue(yyValue, yyError);
    }

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.EmptyDefinition.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEmptyDefinition(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(";")) {

      yyValue = GNode.create("EmptyDefinition", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("empty definition expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Annotations.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  public Result pAnnotations(final int yyStart) throws IOException {
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative 1.

    yyState.mark();
    yyValue = yyState.annotate(null);

    // Commit the state modification.
    yyState.commit();

    setLocation(yyValue, yyStart);
    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Declaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclaration(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Object     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyBase   = yyOption1;
    yyResult = pKeyword(yyBase);
    if (yyResult.hasValue("__extension__")) {
      final String v$el$1 = "__extension__";

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    } else {
      yyError = yyError.select("'__extension__' expected", yyBase);
    }
    { // Start scope for v$g$1.
      final String v$g$1 = cast(yyOpValue1);

      yyResult = pDeclarationSpecifiers(yyOption1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = null;

        yyResult = pInitializedDeclaratorList(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$2 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$2;
        }
        { // Start scope for l.
          final Node l = cast(yyOpValue1);

          if (yyState.isValid(l)) {

            yyBase   = yyOption1;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue(";")) {

              yyValue = GNode.create("Declaration", v$g$1, v$g$2, l);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            } else {
              yyError = yyError.select("';' expected", yyBase);
            }
          }
        } // End scope for l.
      }
    } // End scope for v$g$1.

    // Done.
    yyError = yyError.select("declaration expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DeclarationSpecifiers.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationSpecifiers(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fDeclarationSpecifiers) 
      yyColumn.chunk1.fDeclarationSpecifiers = pDeclarationSpecifiers$1(yyStart);
    return yyColumn.chunk1.fDeclarationSpecifiers;
  }

  /** Actually parse xtc.lang.c4.C4.DeclarationSpecifiers. */
  private Result pDeclarationSpecifiers$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pDeclarationSpecifierPlus(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Pair<Node> v$g$1 = yyResult.semanticValue();

      yyValue = GNode.createFromPair("DeclarationSpecifiers", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DeclarationSpecifierPlus.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationSpecifierPlus(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    Pair<Node> yyRepValue1;
    Pair<Node> yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pDeclarationSpecifier(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepeated1   = true;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }

    if (yyRepeated1) {
      yyValue = yyRepValue1.reverse();

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DeclarationSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationSpecifier(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <StorageClass>.

    yyResult = pStorageClassSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <TypeSpecifier>.

    yyResult = pTypeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyResult = pTypeSpecContext(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative <TypeQualifier>.

    yyResult = pTypeQualifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("inline")) {
      final String v$g$1 = "inline";

      yyValue = GNode.create("FunctionSpecifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 5.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__inline")) {
      final String v$g$2 = "__inline";

      yyValue = GNode.create("FunctionSpecifier", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 6.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__inline__")) {
      final String v$g$3 = "__inline__";

      yyValue = GNode.create("FunctionSpecifier", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Attribute>.

    yyResult = pAttributeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("declaration specifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.InitializedDeclaratorList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pInitializedDeclaratorList(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <List>.

    yyResult = pInitializedDeclarator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyBase   = yyRepetition1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyResult = pInitializedDeclarator(yyResult.index);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
            continue;
          }
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }
        break;
      }
      { // Start scope for v$g$2.
        final Pair<Node> v$g$2 = yyRepValue1.reverse();

        yyValue = GNode.createFromPair("InitializedDeclaratorList", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$g$2.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.InitializedDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pInitializedDeclarator(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyResult = pAttributeSpecifierList(yyOption1);
    yyError  = yyResult.select(yyError, yyOption1);
    if (yyResult.hasValue()) {
      final Node v$el$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    }
    { // Start scope for v$g$1.
      final Node v$g$1 = yyOpValue1;

      yyResult = pDeclarator(yyOption1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = null;

        yyResult = pSimpleAssemblyExpression(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$2 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$2;
        }
        { // Start scope for v$g$3.
          final Node v$g$3 = yyOpValue1;

          yyOpValue1 = null;

          yyResult = pAttributeSpecifierList(yyOption1);
          yyError  = yyResult.select(yyError, yyOption1);
          if (yyResult.hasValue()) {
            final Node v$el$3 = yyResult.semanticValue();

            yyOption1  = yyResult.index;
            yyOpValue1 = v$el$3;
          }
          { // Start scope for v$g$4.
            final Node v$g$4 = yyOpValue1;

            yyOpValue1 = null;

            yyBase   = yyOption1;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue("=")) {

              yyResult = pInitializer(yyResult.index);
              yyError  = yyResult.select(yyError, yyOption1);
              if (yyResult.hasValue()) {
                final Node v$el$4 = yyResult.semanticValue();

                yyOption1  = yyResult.index;
                yyOpValue1 = v$el$4;
              }
            } else {
              yyError = yyError.select("'=' expected", yyBase);
            }
            { // Start scope for v$g$5.
              final Node v$g$5 = yyOpValue1;

              yyValue = GNode.create("InitializedDeclarator", v$g$1, v$g$2, v$g$3, v$g$4, v$g$5);
              yyValue.setLocation(location(yyStart));

              return new SemanticValue(yyValue, yyOption1, yyError);
            } // End scope for v$g$5.
          } // End scope for v$g$4.
        } // End scope for v$g$3.
      }
    } // End scope for v$g$1.

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.StorageClassSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStorageClassSpecifier(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("auto")) {

      yyValue = GNode.create("AutoSpecifier", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("extern")) {

      yyValue = GNode.create("ExternSpecifier", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("register")) {

      yyValue = GNode.create("RegisterSpecifier", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("static")) {

      yyValue = GNode.create("StaticSpecifier", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 5.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__thread")) {

      yyValue = GNode.create("ThreadSpecifier", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 6.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("typedef")) {

      yyResult = pTypedefContext(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyValue = GNode.create("TypedefSpecifier", false);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("storage class specifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.TypeQualifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pTypeQualifier(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("volatile")) {
      final String v$g$1 = "volatile";

      yyValue = GNode.create("VolatileQualifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__volatile")) {
      final String v$g$2 = "__volatile";

      yyValue = GNode.create("VolatileQualifier", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__volatile__")) {
      final String v$g$3 = "__volatile__";

      yyValue = GNode.create("VolatileQualifier", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("const")) {
      final String v$g$1 = "const";

      yyValue = GNode.create("ConstantQualifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 5.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__const")) {
      final String v$g$2 = "__const";

      yyValue = GNode.create("ConstantQualifier", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 6.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__const__")) {
      final String v$g$3 = "__const__";

      yyValue = GNode.create("ConstantQualifier", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 7.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("restrict")) {
      final String v$g$1 = "restrict";

      yyValue = GNode.create("RestrictQualifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 8.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__restrict")) {
      final String v$g$2 = "__restrict";

      yyValue = GNode.create("RestrictQualifier", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 9.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__restrict__")) {
      final String v$g$3 = "__restrict__";

      yyValue = GNode.create("RestrictQualifier", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("type qualifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.TypeSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pTypeSpecifier(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Enumeration>.

    yyResult = pEnumerationTypeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Structure>.

    yyResult = pStructureTypeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Union>.

    yyResult = pUnionTypeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Floating>.

    yyResult = pFloatingPointTypeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Integer>.

    yyResult = pIntegerTypeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 6.

    yyResult = pIdentifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String id = yyResult.semanticValue();

      if (yyState.isType(toText(id))) {

        yyValue = GNode.create("TypedefName", id);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 7.

    yyResult = pTypeofKeyword(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        final int yyChoice1 = yyResult.index;

        // Nested alternative 1.

        yyResult = pTypeName(yyChoice1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyValue = GNode.create("TypeofSpecifier", v$g$1);
            yyValue.setLocation(location(yyStart));

            return yyResult.createValue(yyValue, yyError);
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }

        // Nested alternative 2.

        yyResult = pCommaExpression(yyChoice1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$2 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyValue = GNode.create("TypeofSpecifier", v$g$2);
            yyValue.setLocation(location(yyStart));

            return yyResult.createValue(yyValue, yyError);
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Alternative 8.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("void")) {

      yyValue = GNode.create("VoidTypeSpecifier", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 9.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__builtin_va_list")) {

      yyValue = GNode.create("VarArgListSpecifier", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("type specifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.EnumerationTypeSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEnumerationTypeSpecifier(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Object     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("enum")) {

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyResult = pAttributeSpecifierList(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$1;
      }
      { // Start scope for v$g$1.
        final Node v$g$1 = cast(yyOpValue1);

        final int yyChoice1 = yyOption1;

        // Nested alternative 1.

        yyOption1  = yyChoice1;
        yyOpValue1 = null;

        yyResult = pIdentifier(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final String v$el$2 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$2;
        }
        { // Start scope for v$g$2.
          final String v$g$2 = cast(yyOpValue1);

          yyBase   = yyOption1;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("{")) {

            yyResult = pEnumeratorList(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$3 = yyResult.semanticValue();

              yyOption1  = yyResult.index;

              yyBase   = yyOption1;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(",")) {

                yyOption1  = yyResult.index;
              } else {
                yyError = yyError.select("',' expected", yyBase);
              }

              yyBase   = yyOption1;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue("}")) {

                yyOption1  = yyResult.index;
                yyOpValue1 = null;

                yyResult = pAttributeSpecifierList(yyOption1);
                yyError  = yyResult.select(yyError, yyOption1);
                if (yyResult.hasValue()) {
                  final Node v$el$3 = yyResult.semanticValue();

                  yyOption1  = yyResult.index;
                  yyOpValue1 = v$el$3;
                }
                { // Start scope for v$g$4.
                  final Node v$g$4 = cast(yyOpValue1);

                  yyValue = GNode.create("EnumerationTypeDefinition", v$g$1, v$g$2, v$g$3, v$g$4);
                  yyValue.setLocation(location(yyStart));

                  return new SemanticValue(yyValue, yyOption1, yyError);
                } // End scope for v$g$4.
              } else {
                yyError = yyError.select("'}' expected", yyBase);
              }
            }
          } else {
            yyError = yyError.select("'{' expected", yyBase);
          }
        } // End scope for v$g$2.

        // Nested alternative 2.

        yyResult = pIdentifier(yyChoice1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String v$g$2 = yyResult.semanticValue();

          yyValue = GNode.create("EnumerationTypeReference", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        }
      } // End scope for v$g$1.
    }

    // Done.
    yyError = yyError.select("enumeration type specifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.EnumeratorList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEnumeratorList(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <List>.

    yyResult = pEnumerator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyBase   = yyRepetition1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyResult = pEnumerator(yyResult.index);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
            continue;
          }
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }
        break;
      }
      { // Start scope for v$g$2.
        final Pair<Node> v$g$2 = yyRepValue1.reverse();

        yyValue = GNode.createFromPair("EnumeratorList", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$g$2.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Enumerator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEnumerator(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Enumerator>.

    yyResult = pIdentifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String id = yyResult.semanticValue();

      yyState.bind(toText(id), false);

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyBase   = yyOption1;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("=")) {

        yyResult = pConditionalExpression(yyResult.index);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$1 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$1;
        }
      } else {
        yyError = yyError.select("'=' expected", yyBase);
      }
      { // Start scope for v$g$1.
        final Node v$g$1 = yyOpValue1;

        yyValue = GNode.create("Enumerator", id, v$g$1);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyOption1, yyError);
      } // End scope for v$g$1.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.StructureTypeSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStructureTypeSpecifier(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Object     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("struct")) {

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyResult = pAttributeSpecifierList(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$1;
      }
      { // Start scope for v$g$1.
        final Node v$g$1 = cast(yyOpValue1);

        final int yyChoice1 = yyOption1;

        // Nested alternative 1.

        yyOption1  = yyChoice1;
        yyOpValue1 = null;

        yyResult = pIdentifier(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final String v$el$2 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$2;
        }
        { // Start scope for v$g$2.
          final String v$g$2 = cast(yyOpValue1);

          yyBase   = yyOption1;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("{")) {

            yyResult = pPushScope(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {

              yyResult = pEnterStructure(yyResult.index);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {

                final int yyChoice2 = yyResult.index;

                // Nested alternative 1.

                yyResult = pStructureDeclarationList(yyChoice2);
                yyError  = yyResult.select(yyError);
                if (yyResult.hasValue()) {
                  final Node v$g$3 = yyResult.semanticValue();

                  yyBase   = yyResult.index;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyResult = pExitStructure(yyResult.index);
                    yyError  = yyResult.select(yyError);
                    if (yyResult.hasValue()) {

                      yyResult = pPopScope(yyResult.index);
                      yyError  = yyResult.select(yyError);
                      if (yyResult.hasValue()) {

                        yyOption1  = yyResult.index;
                        yyOpValue1 = null;

                        yyResult = pAttributeSpecifierList(yyOption1);
                        yyError  = yyResult.select(yyError, yyOption1);
                        if (yyResult.hasValue()) {
                          final Node v$el$3 = yyResult.semanticValue();

                          yyOption1  = yyResult.index;
                          yyOpValue1 = v$el$3;
                        }
                        { // Start scope for v$g$4.
                          final Node v$g$4 = cast(yyOpValue1);

                          yyValue = GNode.create("StructureTypeDefinition", v$g$1, v$g$2, v$g$3, v$g$4);
                          yyValue.setLocation(location(yyStart));

                          return new SemanticValue(yyValue, yyOption1, yyError);
                        } // End scope for v$g$4.
                      }
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                }

                // Nested alternative 2.

                yyResult = pAspectStructureDeclarationList(yyChoice2);
                yyError  = yyResult.select(yyError);
                if (yyResult.hasValue()) {
                  final Node v$g$3 = yyResult.semanticValue();

                  yyBase   = yyResult.index;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyResult = pExitStructure(yyResult.index);
                    yyError  = yyResult.select(yyError);
                    if (yyResult.hasValue()) {

                      yyResult = pPopScope(yyResult.index);
                      yyError  = yyResult.select(yyError);
                      if (yyResult.hasValue()) {

                        yyOption1  = yyResult.index;
                        yyOpValue1 = null;

                        yyResult = pAttributeSpecifierList(yyOption1);
                        yyError  = yyResult.select(yyError, yyOption1);
                        if (yyResult.hasValue()) {
                          final Node v$el$3 = yyResult.semanticValue();

                          yyOption1  = yyResult.index;
                          yyOpValue1 = v$el$3;
                        }
                        { // Start scope for v$g$4.
                          final Node v$g$4 = cast(yyOpValue1);

                          yyValue = GNode.create("AspectStructureTypeDefinition", v$g$1, v$g$2, v$g$3, v$g$4);
                          yyValue.setLocation(location(yyStart));

                          return new SemanticValue(yyValue, yyOption1, yyError);
                        } // End scope for v$g$4.
                      }
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                }
              }
            }
          } else {
            yyError = yyError.select("'{' expected", yyBase);
          }
        } // End scope for v$g$2.

        // Nested alternative 2.

        yyResult = pIdentifier(yyChoice1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String v$g$2 = yyResult.semanticValue();

          yyValue = GNode.create("StructureTypeReference", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        }
      } // End scope for v$g$1.
    }

    // Done.
    yyError = yyError.select("structure type specifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.UnionTypeSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pUnionTypeSpecifier(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Object     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("union")) {

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyResult = pAttributeSpecifierList(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$1;
      }
      { // Start scope for v$g$1.
        final Node v$g$1 = cast(yyOpValue1);

        final int yyChoice1 = yyOption1;

        // Nested alternative 1.

        yyOption1  = yyChoice1;
        yyOpValue1 = null;

        yyResult = pIdentifier(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final String v$el$2 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$2;
        }
        { // Start scope for v$g$2.
          final String v$g$2 = cast(yyOpValue1);

          yyBase   = yyOption1;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("{")) {

            yyResult = pPushScope(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {

              yyResult = pEnterStructure(yyResult.index);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {

                yyResult = pStructureDeclarationList(yyResult.index);
                yyError  = yyResult.select(yyError);
                if (yyResult.hasValue()) {
                  final Node v$g$3 = yyResult.semanticValue();

                  yyBase   = yyResult.index;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyResult = pExitStructure(yyResult.index);
                    yyError  = yyResult.select(yyError);
                    if (yyResult.hasValue()) {

                      yyResult = pPopScope(yyResult.index);
                      yyError  = yyResult.select(yyError);
                      if (yyResult.hasValue()) {

                        yyOption1  = yyResult.index;
                        yyOpValue1 = null;

                        yyResult = pAttributeSpecifierList(yyOption1);
                        yyError  = yyResult.select(yyError, yyOption1);
                        if (yyResult.hasValue()) {
                          final Node v$el$3 = yyResult.semanticValue();

                          yyOption1  = yyResult.index;
                          yyOpValue1 = v$el$3;
                        }
                        { // Start scope for v$g$4.
                          final Node v$g$4 = cast(yyOpValue1);

                          yyValue = GNode.create("UnionTypeDefinition", v$g$1, v$g$2, v$g$3, v$g$4);
                          yyValue.setLocation(location(yyStart));

                          return new SemanticValue(yyValue, yyOption1, yyError);
                        } // End scope for v$g$4.
                      }
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                }
              }
            }
          } else {
            yyError = yyError.select("'{' expected", yyBase);
          }
        } // End scope for v$g$2.

        // Nested alternative 2.

        yyResult = pIdentifier(yyChoice1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String v$g$2 = yyResult.semanticValue();

          yyValue = GNode.create("UnionTypeReference", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        }
      } // End scope for v$g$1.
    }

    // Done.
    yyError = yyError.select("union type specifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.StructureDeclarationList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStructureDeclarationList(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Regular>.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pAnnotatedStructureDeclaration(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepeated1   = true;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }

    if (yyRepeated1) {
      final Pair<Node> v$g$1 = yyRepValue1.reverse();

      yyResult = pAnnotations(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = GNode.create("StructureDeclarationList", v$g$1.size() + 1).
          addAll(v$g$1).add(v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative <Empty>.

    if (GCC) {

      yyResult = pAnnotations(yyStart);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyValue = GNode.create("StructureDeclarationList", v$g$3);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("structure declaration list expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AnnotatedStructureDeclaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAnnotatedStructureDeclaration(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative 1.

    yyState.mark();

    yyResult = pStructureDeclaration(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node d = yyResult.semanticValue();

      yyValue = yyState.annotate(d);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.StructureDeclaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStructureDeclaration(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    boolean    yyRepeated1;
    int        yyOption1;
    String     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Declaration>.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyBase   = yyOption1;
    yyResult = pKeyword(yyBase);
    if (yyResult.hasValue("__extension__")) {
      final String v$el$1 = "__extension__";

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    } else {
      yyError = yyError.select("'__extension__' expected", yyBase);
    }
    { // Start scope for v$g$1.
      final String v$g$1 = yyOpValue1;

      yyResult = pSpecifierQualifierList(yyOption1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyResult = pOptionalStructureDeclaratorList(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$3 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(";")) {

            yyOption1  = yyResult.index;

            if (GCC) {

              yyRepetition1 = yyOption1;
              yyRepeated1   = false;
              while (true) {

                yyBase   = yyRepetition1;
                yyResult = pSymbol(yyBase);
                if (yyResult.hasValue(";")) {

                  yyRepetition1 = yyResult.index;
                  yyRepeated1   = true;
                  continue;
                } else {
                  yyError = yyError.select("';' expected", yyBase);
                }
                break;
              }

              if (yyRepeated1) {

                yyOption1  = yyRepetition1;
              }
            }

            yyValue = GNode.create("StructureDeclaration", v$g$1, v$g$2, v$g$3);
            yyValue.setLocation(location(yyStart));

            return new SemanticValue(yyValue, yyOption1, yyError);
          } else {
            yyError = yyError.select("';' expected", yyBase);
          }
        }
      }
    } // End scope for v$g$1.

    // Done.
    yyError = yyError.select("structure declaration expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.SpecifierQualifierList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSpecifierQualifierList(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fSpecifierQualifierList) 
      yyColumn.chunk1.fSpecifierQualifierList = pSpecifierQualifierList$1(yyStart);
    return yyColumn.chunk1.fSpecifierQualifierList;
  }

  /** Actually parse xtc.lang.c4.C4.SpecifierQualifierList. */
  private Result pSpecifierQualifierList$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSpecifierQualifierPlus(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Pair<Node> v$g$1 = yyResult.semanticValue();

      yyValue = GNode.createFromPair("SpecifierQualifierList", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.SpecifierQualifierPlus.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSpecifierQualifierPlus(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    Pair<Node> yyRepValue1;
    Pair<Node> yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pSpecifierQualifier(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepeated1   = true;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }

    if (yyRepeated1) {
      yyValue = yyRepValue1.reverse();

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.SpecifierQualifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSpecifierQualifier(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <TypeSpecifier>.

    yyResult = pTypeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyResult = pTypeSpecContext(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative <TypeQualifier>.

    yyResult = pTypeQualifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Attribute>.

    yyResult = pAttributeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.OptionalStructureDeclaratorList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pOptionalStructureDeclaratorList(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fOptionalStructureDeclaratorList) 
      yyColumn.chunk1.fOptionalStructureDeclaratorList = pOptionalStructureDeclaratorList$1(yyStart);
    return yyColumn.chunk1.fOptionalStructureDeclaratorList;
  }

  /** Actually parse xtc.lang.c4.C4.OptionalStructureDeclaratorList. */
  private Result pOptionalStructureDeclaratorList$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <List>.

    yyResult = pStructureDeclaratorList(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Null>.

    if (GCC) {
      { // Start scope for yyValue.
        yyValue = null;

        return new SemanticValue(yyValue, yyStart, yyError);
      } // End scope for yyValue.
    }

    // Done.
    yyError = yyError.select("optional structure declarator list expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.StructureDeclaratorList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStructureDeclaratorList(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <List>.

    yyResult = pStructureDeclarator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyBase   = yyRepetition1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyResult = pStructureDeclarator(yyResult.index);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
            continue;
          }
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }
        break;
      }
      { // Start scope for v$g$2.
        final Pair<Node> v$g$2 = yyRepValue1.reverse();

        yyValue = GNode.createFromPair("StructureDeclaratorList", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$g$2.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.StructureDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStructureDeclarator(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyResult = pAttributeSpecifierList(yyOption1);
    yyError  = yyResult.select(yyError, yyOption1);
    if (yyResult.hasValue()) {
      final Node v$el$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    }
    { // Start scope for v$g$1.
      final Node v$g$1 = yyOpValue1;

      yyOpValue1 = null;

      yyResult = pDeclarator(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$2;
      }
      { // Start scope for v$g$2.
        final Node v$g$2 = yyOpValue1;

        yyBase   = yyOption1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(":")) {

          yyResult = pConditionalExpression(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Node v$g$3 = yyResult.semanticValue();

            yyOption1  = yyResult.index;
            yyOpValue1 = null;

            yyResult = pAttributeSpecifierList(yyOption1);
            yyError  = yyResult.select(yyError, yyOption1);
            if (yyResult.hasValue()) {
              final Node v$el$3 = yyResult.semanticValue();

              yyOption1  = yyResult.index;
              yyOpValue1 = v$el$3;
            }
            { // Start scope for v$g$4.
              final Node v$g$4 = yyOpValue1;

              yyValue = GNode.create("BitField", v$g$1, v$g$2, v$g$3, v$g$4);
              yyValue.setLocation(location(yyStart));

              return new SemanticValue(yyValue, yyOption1, yyError);
            } // End scope for v$g$4.
          }
        } else {
          yyError = yyError.select("':' expected", yyBase);
        }
      } // End scope for v$g$2.
    } // End scope for v$g$1.

    // Alternative <Simple>.

    yyResult = pAttributedDeclarator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AttributedDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAttributedDeclarator(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fAttributedDeclarator) 
      yyColumn.chunk1.fAttributedDeclarator = pAttributedDeclarator$1(yyStart);
    return yyColumn.chunk1.fAttributedDeclarator;
  }

  /** Actually parse xtc.lang.c4.C4.AttributedDeclarator. */
  private Result pAttributedDeclarator$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyResult = pAttributeSpecifierList(yyOption1);
    yyError  = yyResult.select(yyError, yyOption1);
    if (yyResult.hasValue()) {
      final Node v$el$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    }
    { // Start scope for v$g$1.
      final Node v$g$1 = yyOpValue1;

      yyResult = pDeclarator(yyOption1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = null;

        yyResult = pAttributeSpecifierList(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$2 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$2;
        }
        { // Start scope for v$g$3.
          final Node v$g$3 = yyOpValue1;

          yyValue = GNode.create("AttributedDeclarator", v$g$1, v$g$2, v$g$3);
          yyValue.setLocation(location(yyStart));

          return new SemanticValue(yyValue, yyOption1, yyError);
        } // End scope for v$g$3.
      }
    } // End scope for v$g$1.

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Declarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarator(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fDeclarator) 
      yyColumn.chunk1.fDeclarator = pDeclarator$1(yyStart);
    return yyColumn.chunk1.fDeclarator;
  }

  /** Actually parse xtc.lang.c4.C4.Declarator. */
  private Result pDeclarator$1(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Pointer>.

    yyResult = pPointerDeclarator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Direct>.

    yyResult = pDirectDeclarator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.PointerDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPointerDeclarator(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pPointer(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyResult = pDirectDeclarator(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = GNode.create("PointerDeclarator", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Pointer.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPointer(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fPointer) 
      yyColumn.chunk1.fPointer = pPointer$1(yyStart);
    return yyColumn.chunk1.fPointer;
  }

  /** Actually parse xtc.lang.c4.C4.Pointer. */
  private Result pPointer$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("*")) {

      yyResult = pTypeQualifierList(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = null;

        yyResult = pPointer(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$1 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$1;
        }
        { // Start scope for v$g$2.
          final Node v$g$2 = yyOpValue1;

          yyValue = GNode.create("Pointer", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return new SemanticValue(yyValue, yyOption1, yyError);
        } // End scope for v$g$2.
      }
    }

    // Done.
    yyError = yyError.select("pointer expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.TypeQualifierList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pTypeQualifierList(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pTypeQualifierList$$Choice1(yyRepetition1);
      yyError  = yyResult.select(yyError, yyRepetition1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }
    { // Start scope for v$g$1.
      final Pair<Node> v$g$1 = yyRepValue1.reverse();

      yyValue = GNode.createFromPair("TypeQualifierList", v$g$1);
      yyValue.setLocation(location(yyStart));

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    } // End scope for v$g$1.
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.TypeQualifierList$$Choice1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pTypeQualifierList$$Choice1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pTypeQualifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pAttributeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DirectDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDirectDeclarator(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyBase;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <FullBase>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("(")) {

      yyResult = pAttributedDeclarator(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$7 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(")")) {

          yyRepetition1 = yyResult.index;
          yyRepValue1   = Pair.empty();
          while (true) {

            yyResult = pDirectDeclarator$$Tail1(yyRepetition1);
            yyError  = yyResult.select(yyError, yyRepetition1);
            if (yyResult.hasValue()) {
              final Action<Node> v$8 = yyResult.semanticValue();

              yyRepetition1 = yyResult.index;
              yyRepValue1   = new Pair<Action<Node>>(v$8, yyRepValue1);
              continue;
            }
            break;
          }
          { // Start scope for v$9.
            final Pair<Action<Node>> v$9 = yyRepValue1.reverse();

            yyValue = apply(v$9, v$g$7, yyStart);

            return new SemanticValue(yyValue, yyRepetition1, yyError);
          } // End scope for v$9.
        } else {
          yyError = yyError.select("')' expected", yyBase);
        }
      }
    }

    // Alternative <SimpleBase>.

    yyResult = pSimpleDeclarator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$10 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pDirectDeclarator$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$11 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$11, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$12.
        final Pair<Action<Node>> v$12 = yyRepValue1.reverse();

        yyValue = apply(v$12, v$g$10, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$12.
    }

    // Done.
    yyError = yyError.select("direct declarator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.DirectDeclarator$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDirectDeclarator$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    int          yyBase;
    int          yyOption1;
    Node         yyOpValue1;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("(")) {

      yyResult = pPushScope(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        final int yyChoice1 = yyResult.index;

        // Nested alternative 1.

        yyResult = pParameterTypeList(yyChoice1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$2 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyResult = pParameterContext(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {

              yyValue = new Action<Node>() {
                public Node run(Node v$1) {
                  return GNode.create("FunctionDeclarator", v$1, v$g$2);
                }};

              return yyResult.createValue(yyValue, yyError);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }

        // Nested alternative 2.

        yyOption1  = yyChoice1;
        yyOpValue1 = null;

        yyResult = pIdentifierList(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$1 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$1;
        }
        { // Start scope for v$g$3.
          final Node v$g$3 = yyOpValue1;

          yyBase   = yyOption1;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyResult = pParameterContext(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {

              yyValue = new Action<Node>() {
                public Node run(Node v$1) {
                  return GNode.create("FunctionDeclarator", v$1, v$g$3);
                }};

              return yyResult.createValue(yyValue, yyError);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        } // End scope for v$g$3.
      }
    }

    // Alternative 2.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("[")) {

      yyResult = pArrayQualifierList(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$4 = yyResult.semanticValue();

        final int yyChoice1 = yyResult.index;

        // Nested alternative 1.

        yyOption1  = yyChoice1;
        yyOpValue1 = null;

        yyResult = pAssignmentExpression(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$2 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$2;
        }
        { // Start scope for v$g$5.
          final Node v$g$5 = yyOpValue1;

          yyBase   = yyOption1;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("]")) {

            yyValue = new Action<Node>() {
              public Node run(Node v$1) {
                return GNode.create("ArrayDeclarator", v$1, v$g$4, v$g$5);
              }};

            return yyResult.createValue(yyValue, yyError);
          } else {
            yyError = yyError.select("']' expected", yyBase);
          }
        } // End scope for v$g$5.

        // Nested alternative 2.

        yyResult = pVariableLength(yyChoice1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$6 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("]")) {

            yyValue = new Action<Node>() {
              public Node run(Node v$1) {
                return GNode.create("ArrayDeclarator", v$1, v$g$4, v$g$6);
              }};

            return yyResult.createValue(yyValue, yyError);
          } else {
            yyError = yyError.select("']' expected", yyBase);
          }
        }
      }
    }

    // Done.
    yyError = yyError.select("direct declarator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.VariableLength.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pVariableLength(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk1) yyColumn.chunk1 = new Chunk1();
    if (null == yyColumn.chunk1.fVariableLength) 
      yyColumn.chunk1.fVariableLength = pVariableLength$1(yyStart);
    return yyColumn.chunk1.fVariableLength;
  }

  /** Actually parse xtc.lang.c4.C4.VariableLength. */
  private Result pVariableLength$1(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("*")) {

      yyValue = GNode.create("VariableLength", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("variable length expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.SimpleDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSimpleDeclarator(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Declarator>.

    yyResult = pIdentifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String id = yyResult.semanticValue();

      yyState.bind(toText(id));

      yyValue = GNode.create("SimpleDeclarator", id);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ParameterTypeList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pParameterTypeList(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fParameterTypeList) 
      yyColumn.chunk2.fParameterTypeList = pParameterTypeList$1(yyStart);
    return yyColumn.chunk2.fParameterTypeList;
  }

  /** Actually parse xtc.lang.c4.C4.ParameterTypeList. */
  private Result pParameterTypeList$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    String     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pParameterList(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyBase   = yyOption1;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(",")) {

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("...")) {
          final String v$el$1 = "...";

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$1;
        } else {
          yyError = yyError.select("'...' expected", yyBase);
        }
      } else {
        yyError = yyError.select("',' expected", yyBase);
      }
      { // Start scope for v$g$2.
        final String v$g$2 = yyOpValue1;

        yyValue = GNode.create("ParameterTypeList", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyOption1, yyError);
      } // End scope for v$g$2.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ParameterList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pParameterList(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pParameterDeclaration(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyBase   = yyRepetition1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyResult = pParameterDeclaration(yyResult.index);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
            continue;
          }
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }
        break;
      }
      { // Start scope for v$g$2.
        final Pair<Node> v$g$2 = yyRepValue1.reverse();

        yyValue = GNode.createFromPair("ParameterList", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$g$2.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ParameterDeclaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pParameterDeclaration(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative 1.

    yyResult = pDeclarationSpecifiers(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyResult = pDeclarator(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = null;

        yyResult = pAttributeSpecifierList(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$1 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$1;
        }
        { // Start scope for v$g$3.
          final Node v$g$3 = yyOpValue1;

          yyValue = GNode.create("ParameterDeclaration", v$g$1, v$g$2, v$g$3);
          yyValue.setLocation(location(yyStart));

          // Commit the state modification.
          yyState.commit();

          return new SemanticValue(yyValue, yyOption1, yyError);
        } // End scope for v$g$3.
      }

      // Nested alternative 2.

      yyOption1  = yyChoice1;
      yyOpValue1 = null;

      yyResult = pAbstractDeclarator(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$2;
      }
      { // Start scope for v$g$4.
        final Node v$g$4 = yyOpValue1;

        yyOpValue1 = null;

        yyResult = pAttributeSpecifierList(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$3 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$3;
        }
        { // Start scope for v$g$5.
          final Node v$g$5 = yyOpValue1;

          yyValue = GNode.create("ParameterDeclaration", v$g$1, v$g$4, v$g$5);
          yyValue.setLocation(location(yyStart));

          // Commit the state modification.
          yyState.commit();

          return new SemanticValue(yyValue, yyOption1, yyError);
        } // End scope for v$g$5.
      } // End scope for v$g$4.
    }

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AttributedAbstractDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAttributedAbstractDeclarator(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyResult = pAttributeSpecifierList(yyOption1);
    yyError  = yyResult.select(yyError, yyOption1);
    if (yyResult.hasValue()) {
      final Node v$el$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    }
    { // Start scope for v$g$1.
      final Node v$g$1 = yyOpValue1;

      yyResult = pAbstractDeclarator(yyOption1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = GNode.create("AttributedAbstractDeclarator", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    } // End scope for v$g$1.

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AbstractDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAbstractDeclarator(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fAbstractDeclarator) 
      yyColumn.chunk2.fAbstractDeclarator = pAbstractDeclarator$1(yyStart);
    return yyColumn.chunk2.fAbstractDeclarator;
  }

  /** Actually parse xtc.lang.c4.C4.AbstractDeclarator. */
  private Result pAbstractDeclarator$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyResult = pPointer(yyOption1);
    yyError  = yyResult.select(yyError, yyOption1);
    if (yyResult.hasValue()) {
      final Node v$el$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    }
    { // Start scope for p.
      final Node p = yyOpValue1;

      yyResult = pDirectAbstractDeclarator(yyOption1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node d = yyResult.semanticValue();

        if ((null != p) || (null != d)) {

          yyValue = GNode.create("AbstractDeclarator", p, d);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        }
      }
    } // End scope for p.

    // Done.
    yyError = yyError.select("abstract declarator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DirectAbstractDeclarator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDirectAbstractDeclarator(final int yyStart) 
    throws IOException {

    Result             yyResult;
    int                yyBase;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Parenthesized>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("(")) {

      yyResult = pAttributedAbstractDeclarator(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$7 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(")")) {

          yyRepetition1 = yyResult.index;
          yyRepValue1   = Pair.empty();
          while (true) {

            yyResult = pDirectAbstractDeclarator$$Tail1(yyRepetition1);
            yyError  = yyResult.select(yyError, yyRepetition1);
            if (yyResult.hasValue()) {
              final Action<Node> v$8 = yyResult.semanticValue();

              yyRepetition1 = yyResult.index;
              yyRepValue1   = new Pair<Action<Node>>(v$8, yyRepValue1);
              continue;
            }
            break;
          }
          { // Start scope for v$9.
            final Pair<Action<Node>> v$9 = yyRepValue1.reverse();

            yyValue = apply(v$9, v$g$7, yyStart);

            return new SemanticValue(yyValue, yyRepetition1, yyError);
          } // End scope for v$9.
        } else {
          yyError = yyError.select("')' expected", yyBase);
        }
      }
    }

    // Alternative <Empty>.

    yyRepetition1 = yyStart;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pDirectAbstractDeclarator$$Tail1(yyRepetition1);
      yyError  = yyResult.select(yyError, yyRepetition1);
      if (yyResult.hasValue()) {
        final Action<Node> v$11 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepValue1   = new Pair<Action<Node>>(v$11, yyRepValue1);
        continue;
      }
      break;
    }
    { // Start scope for v$12.
      final Pair<Action<Node>> v$12 = yyRepValue1.reverse();

      yyValue = apply(v$12, null, yyStart);

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    } // End scope for v$12.
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal 
   * xtc.lang.c4.C4.DirectAbstractDeclarator$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDirectAbstractDeclarator$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    int          yyBase;
    int          yyOption1;
    Node         yyOpValue1;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("[")) {
      final String v$g$2 = "[";

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyOption1  = yyChoice1;
      yyOpValue1 = null;

      yyResult = pAssignmentExpression(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$1;
      }
      { // Start scope for v$g$3.
        final Node v$g$3 = yyOpValue1;

        yyBase   = yyOption1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("]")) {

          yyValue = new Action<Node>() {
            public Node run(Node v$1) {
              return GNode.create("DirectAbstractDeclarator", v$1, v$g$2, v$g$3);
            }};

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("']' expected", yyBase);
        }
      } // End scope for v$g$3.

      // Nested alternative 2.

      yyResult = pVariableLength(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$4 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("]")) {

          yyValue = new Action<Node>() {
            public Node run(Node v$1) {
              return GNode.create("DirectAbstractDeclarator", v$1, v$g$2, v$g$4);
            }};

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("']' expected", yyBase);
        }
      }
    }

    // Alternative 2.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("(")) {
      final String v$g$5 = "(";

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyResult = pParameterTypeList(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$2;
      }
      { // Start scope for v$g$6.
        final Node v$g$6 = yyOpValue1;

        yyBase   = yyOption1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(")")) {

          yyValue = new Action<Node>() {
            public Node run(Node v$1) {
              return GNode.create("DirectAbstractDeclarator", v$1, v$g$5, v$g$6);
            }};

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("')' expected", yyBase);
        }
      } // End scope for v$g$6.
    }

    // Done.
    yyError = yyError.select("direct abstract declarator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.IdentifierList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pIdentifierList(final int yyStart) throws IOException {
    Result       yyResult;
    int          yyBase;
    int          yyRepetition1;
    Pair<String> yyRepValue1;
    Node         yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pIdentifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String id1 = yyResult.semanticValue();

      yyState.bind(toText(id1));

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyBase   = yyRepetition1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyResult = pIdentifier(yyResult.index);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final String id2 = yyResult.semanticValue();

            yyState.bind(toText(id2));

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<String>(id2, yyRepValue1);
            continue;
          }
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }
        break;
      }
      { // Start scope for v$g$1.
        final Pair<String> v$g$1 = yyRepValue1.reverse();

        yyValue = GNode.createFromPair("IdentifierList", id1, v$g$1);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$g$1.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ArrayQualifierList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pArrayQualifierList(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pArrayQualifierList$$Choice1(yyRepetition1);
      yyError  = yyResult.select(yyError, yyRepetition1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }
    { // Start scope for v$g$1.
      final Pair<Node> v$g$1 = yyRepValue1.reverse();

      yyValue = GNode.createFromPair("ArrayQualifierList", v$g$1);
      yyValue.setLocation(location(yyStart));

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    } // End scope for v$g$1.
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.ArrayQualifierList$$Choice1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pArrayQualifierList$$Choice1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("static")) {

      yyValue = GNode.create("StaticSpecifier", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("volatile")) {
      final String v$g$1 = "volatile";

      yyValue = GNode.create("VolatileQualifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__volatile")) {
      final String v$g$2 = "__volatile";

      yyValue = GNode.create("VolatileQualifier", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__volatile__")) {
      final String v$g$3 = "__volatile__";

      yyValue = GNode.create("VolatileQualifier", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 5.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("restrict")) {
      final String v$g$1 = "restrict";

      yyValue = GNode.create("RestrictQualifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 6.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__restrict")) {
      final String v$g$2 = "__restrict";

      yyValue = GNode.create("RestrictQualifier", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 7.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__restrict__")) {
      final String v$g$3 = "__restrict__";

      yyValue = GNode.create("RestrictQualifier", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 8.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("const")) {
      final String v$g$1 = "const";

      yyValue = GNode.create("ConstantQualifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 9.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__const")) {
      final String v$g$2 = "__const";

      yyValue = GNode.create("ConstantQualifier", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 10.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__const__")) {
      final String v$g$3 = "__const__";

      yyValue = GNode.create("ConstantQualifier", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 11.

    yyResult = pAttributeSpecifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("array qualifier list expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.FloatingPointTypeSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pFloatingPointTypeSpecifier(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("_Complex")) {
      final String v$g$1 = "_Complex";

      yyValue = GNode.create("Complex", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__complex__")) {
      final String v$g$2 = "__complex__";

      yyValue = GNode.create("Complex", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("double")) {

      yyValue = GNode.create("Double", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("float")) {

      yyValue = GNode.create("Float", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("floating point type specifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.IntegerTypeSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pIntegerTypeSpecifier(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("long")) {

      yyValue = GNode.create("Long", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("int")) {

      yyValue = GNode.create("Int", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("short")) {

      yyValue = GNode.create("Short", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("char")) {

      yyValue = GNode.create("Char", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 5.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("_Bool")) {

      yyValue = GNode.create("Bool", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 6.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("unsigned")) {

      yyValue = GNode.create("Unsigned", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 7.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("signed")) {
      final String v$g$1 = "signed";

      yyValue = GNode.create("Signed", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 8.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__signed")) {
      final String v$g$2 = "__signed";

      yyValue = GNode.create("Signed", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 9.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__signed__")) {
      final String v$g$3 = "__signed__";

      yyValue = GNode.create("Signed", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("integer type specifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.TypeofKeyword.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pTypeofKeyword(final int yyStart) throws IOException {
    Result     yyResult;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("typeof")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__typeof")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__typeof__")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("typeof keyword expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Initializer.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pInitializer(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Complex>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("{")) {

      yyResult = pInitializerList(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        yyValue = yyResult.semanticValue();

        yyOption1  = yyResult.index;

        yyBase   = yyOption1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyOption1  = yyResult.index;
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }

        yyBase   = yyOption1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("}")) {

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("'}' expected", yyBase);
        }
      }
    }

    // Alternative <Simple>.

    yyResult = pAssignmentExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("initializer expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.InitializerList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pInitializerList(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pInitializerListEntry(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyBase   = yyRepetition1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyResult = pInitializerListEntry(yyResult.index);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
            continue;
          }
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }
        break;
      }
      { // Start scope for v$g$2.
        final Pair<Node> v$g$2 = yyRepValue1.reverse();

        yyValue = GNode.createFromPair("InitializerList", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$g$2.
    }

    // Alternative 2.

    if (GCC) {

      yyValue = GNode.create("InitializerList", false);
      yyValue.setLocation(location(yyStart));

      return new SemanticValue(yyValue, yyStart, yyError);
    }

    // Done.
    yyError = yyError.select("initializer list expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.InitializerListEntry.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pInitializerListEntry(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyResult = pDesignation(yyOption1);
    yyError  = yyResult.select(yyError, yyOption1);
    if (yyResult.hasValue()) {
      final Node v$el$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    }
    { // Start scope for v$g$1.
      final Node v$g$1 = yyOpValue1;

      yyResult = pInitializer(yyOption1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = GNode.create("InitializerListEntry", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    } // End scope for v$g$1.

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Designation.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDesignation(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    boolean    yyRepeated1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Standard>.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pDesignator(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepeated1   = true;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }

    if (yyRepeated1) {
      final Pair<Node> v$g$1 = yyRepValue1.reverse();

      yyBase   = yyRepetition1;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("=")) {

        yyValue = GNode.createFromPair("Designation", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      } else {
        yyError = yyError.select("'=' expected", yyBase);
      }
    }

    // Alternative 2.

    if (GCC) {

      final int yyChoice1 = yyStart;

      // Nested alternative 1.

      yyResult = pObsoleteArrayDesignation(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        yyValue = yyResult.semanticValue();

        return yyResult.createValue(yyValue, yyError);
      }

      // Nested alternative 2.

      yyResult = pObsoleteFieldDesignation(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        yyValue = yyResult.semanticValue();

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("designation expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Designator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDesignator(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Array>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("[")) {
      final String v$g$1 = "[";

      yyResult = pConditionalExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("]")) {

          yyValue = GNode.create("Designator", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("']' expected", yyBase);
        }
      }
    }

    // Alternative <ArrayRange>.

    if (GCC) {

      yyResult = pSymbol(yyStart);
      if (yyResult.hasValue("[")) {
        final String v$g$3 = "[";

        yyResult = pConditionalExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$4 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("...")) {

            yyResult = pConditionalExpression(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$5 = yyResult.semanticValue();

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue("]")) {

                yyValue = GNode.create("Designator", v$g$3, v$g$4, v$g$5);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              } else {
                yyError = yyError.select("']' expected", yyBase);
              }
            }
          } else {
            yyError = yyError.select("'...' expected", yyBase);
          }
        }
      }
    }

    // Alternative <Structure>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(".")) {
      final String v$g$6 = ".";

      yyResult = pPrimaryIdentifier(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$7 = yyResult.semanticValue();

        yyValue = GNode.create("Designator", v$g$6, v$g$7);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("designator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ObsoleteArrayDesignation.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pObsoleteArrayDesignation(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("[")) {
      final String v$g$1 = "[";

      yyResult = pConditionalExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        final int yyChoice1 = yyResult.index;

        // Nested alternative 1.

        yyBase   = yyChoice1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("]")) {

          yyValue = GNode.create("ObsoleteArrayDesignation", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("']' expected", yyBase);
        }

        // Nested alternative 2.

        yyBase   = yyChoice1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("...")) {

          yyResult = pConditionalExpression(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Node v$g$3 = yyResult.semanticValue();

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue("]")) {

              yyValue = GNode.create("ObsoleteArrayDesignation", v$g$1, v$g$2, v$g$3);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            } else {
              yyError = yyError.select("']' expected", yyBase);
            }
          }
        } else {
          yyError = yyError.select("'...' expected", yyBase);
        }
      }
    }

    // Done.
    yyError = yyError.select("obsolete array designation expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ObsoleteFieldDesignation.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pObsoleteFieldDesignation(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pIdentifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$1 = yyResult.semanticValue();

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(":")) {

        yyValue = GNode.create("ObsoleteFieldDesignation", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      } else {
        yyError = yyError.select("':' expected", yyBase);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.TypeName.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pTypeName(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fTypeName) 
      yyColumn.chunk2.fTypeName = pTypeName$1(yyStart);
    return yyColumn.chunk2.fTypeName;
  }

  /** Actually parse xtc.lang.c4.C4.TypeName. */
  private Result pTypeName$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative 1.

    yyResult = pSpecifierQualifierList(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyResult = pAbstractDeclarator(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$1;
      }
      { // Start scope for v$g$2.
        final Node v$g$2 = yyOpValue1;

        yyValue = GNode.create("TypeName", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        // Commit the state modification.
        yyState.commit();

        return new SemanticValue(yyValue, yyOption1, yyError);
      } // End scope for v$g$2.
    }

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AttributeSpecifierList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAttributeSpecifierList(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fAttributeSpecifierList) 
      yyColumn.chunk2.fAttributeSpecifierList = pAttributeSpecifierList$1(yyStart);
    return yyColumn.chunk2.fAttributeSpecifierList;
  }

  /** Actually parse xtc.lang.c4.C4.AttributeSpecifierList. */
  private Result pAttributeSpecifierList$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pAttributeSpecifierPlus(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Pair<Node> v$g$1 = yyResult.semanticValue();

      yyValue = GNode.createFromPair("AttributeSpecifierList", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AttributeSpecifierPlus.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAttributeSpecifierPlus(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    Pair<Node> yyRepValue1;
    Pair<Node> yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pAttributeSpecifier(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepeated1   = true;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }

    if (yyRepeated1) {
      yyValue = yyRepValue1.reverse();

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AttributeSpecifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAttributeSpecifier(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fAttributeSpecifier) 
      yyColumn.chunk2.fAttributeSpecifier = pAttributeSpecifier$1(yyStart);
    return yyColumn.chunk2.fAttributeSpecifier;
  }

  /** Actually parse xtc.lang.c4.C4.AttributeSpecifier. */
  private Result pAttributeSpecifier$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pAttributeKeyword(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("(")) {

          yyOption1  = yyResult.index;
          yyOpValue1 = null;

          yyResult = pAttributeList(yyOption1);
          yyError  = yyResult.select(yyError, yyOption1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyOption1  = yyResult.index;
            yyOpValue1 = v$el$1;
          }
          { // Start scope for v$g$1.
            final Node v$g$1 = yyOpValue1;

            yyBase   = yyOption1;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue(")")) {

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(")")) {

                yyValue = GNode.create("AttributeSpecifier", v$g$1);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              } else {
                yyError = yyError.select("')' expected", yyBase);
              }
            } else {
              yyError = yyError.select("')' expected", yyBase);
            }
          } // End scope for v$g$1.
        } else {
          yyError = yyError.select("'(' expected", yyBase);
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AttributeKeyword.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAttributeKeyword(final int yyStart) throws IOException {
    Result     yyResult;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__attribute")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__attribute__")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("attribute keyword expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AttributeList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAttributeList(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pAttributeListEntry(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyBase   = yyRepetition1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyResult = pAttributeListEntry(yyResult.index);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
            continue;
          }
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }
        break;
      }
      { // Start scope for v$g$2.
        final Pair<Node> v$g$2 = yyRepValue1.reverse();

        yyValue = GNode.createFromPair("AttributeList", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$g$2.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AttributeListEntry.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAttributeListEntry(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    int        yyOption2;
    Node       yyOpValue2;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pWord(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$1 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyBase   = yyOption1;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyOption2  = yyResult.index;
        yyOpValue2 = null;

        yyResult = pExpressionList(yyOption2);
        yyError  = yyResult.select(yyError, yyOption2);
        if (yyResult.hasValue()) {
          final Node v$el$2 = yyResult.semanticValue();

          yyOption2  = yyResult.index;
          yyOpValue2 = v$el$2;
        }
        { // Start scope for v$el$1.
          final Node v$el$1 = yyOpValue2;

          yyBase   = yyOption2;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyOption1  = yyResult.index;
            yyOpValue1 = v$el$1;
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        } // End scope for v$el$1.
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
      { // Start scope for v$g$2.
        final Node v$g$2 = yyOpValue1;

        yyValue = GNode.create("AttributeListEntry", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyOption1, yyError);
      } // End scope for v$g$2.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Statement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStatement(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fStatement) 
      yyColumn.chunk2.fStatement = pStatement$1(yyStart);
    return yyColumn.chunk2.fStatement;
  }

  /** Actually parse xtc.lang.c4.C4.Statement. */
  private Result pStatement$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pCommaExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(";")) {

        yyValue = GNode.create("ExpressionStatement", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      } else {
        yyError = yyError.select("';' expected", yyBase);
      }
    }

    // Alternative <Compound>.

    yyResult = pCompoundStatement(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("if")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pCommaExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyResult = pStatement(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              final int yyChoice1 = yyResult.index;

              // Nested alternative 1.

              yyBase   = yyChoice1;
              yyResult = pKeyword(yyBase);
              if (yyResult.hasValue("else")) {

                yyResult = pStatement(yyResult.index);
                yyError  = yyResult.select(yyError);
                if (yyResult.hasValue()) {
                  final Node v$g$3 = yyResult.semanticValue();

                  yyValue = GNode.create("IfElseStatement", v$g$1, v$g$2, v$g$3);
                  yyValue.setLocation(location(yyStart));

                  return yyResult.createValue(yyValue, yyError);
                }
              } else {
                yyError = yyError.select("'else' expected", yyBase);
              }

              // Nested alternative 2.

              yyValue = GNode.create("IfStatement", v$g$1, v$g$2);
              yyValue.setLocation(location(yyStart));

              return new SemanticValue(yyValue, yyChoice1, yyError);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("while")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pCommaExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyResult = pStatement(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              yyValue = GNode.create("WhileStatement", v$g$1, v$g$2);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Alternative 5.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("do")) {

      yyResult = pStatement(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pKeyword(yyBase);
        if (yyResult.hasValue("while")) {

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("(")) {

            yyResult = pCommaExpression(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(")")) {

                yyBase   = yyResult.index;
                yyResult = pSymbol(yyBase);
                if (yyResult.hasValue(";")) {

                  yyValue = GNode.create("DoStatement", v$g$1, v$g$2);
                  yyValue.setLocation(location(yyStart));

                  return yyResult.createValue(yyValue, yyError);
                } else {
                  yyError = yyError.select("';' expected", yyBase);
                }
              } else {
                yyError = yyError.select("')' expected", yyBase);
              }
            }
          } else {
            yyError = yyError.select("'(' expected", yyBase);
          }
        } else {
          yyError = yyError.select("'while' expected", yyBase);
        }
      }
    }

    // Alternative 6.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("for")) {

      yyResult = pPushScope(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("(")) {

          yyResult = pInitialClause(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Node v$g$1 = yyResult.semanticValue();

            yyOption1  = yyResult.index;
            yyOpValue1 = null;

            yyResult = pCommaExpression(yyOption1);
            yyError  = yyResult.select(yyError, yyOption1);
            if (yyResult.hasValue()) {
              final Node v$el$1 = yyResult.semanticValue();

              yyOption1  = yyResult.index;
              yyOpValue1 = v$el$1;
            }
            { // Start scope for v$g$2.
              final Node v$g$2 = yyOpValue1;

              yyBase   = yyOption1;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(";")) {

                yyOption1  = yyResult.index;
                yyOpValue1 = null;

                yyResult = pCommaExpression(yyOption1);
                yyError  = yyResult.select(yyError, yyOption1);
                if (yyResult.hasValue()) {
                  final Node v$el$2 = yyResult.semanticValue();

                  yyOption1  = yyResult.index;
                  yyOpValue1 = v$el$2;
                }
                { // Start scope for v$g$3.
                  final Node v$g$3 = yyOpValue1;

                  yyBase   = yyOption1;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue(")")) {

                    yyResult = pStatement(yyResult.index);
                    yyError  = yyResult.select(yyError);
                    if (yyResult.hasValue()) {
                      final Node v$g$4 = yyResult.semanticValue();

                      yyResult = pPopScope(yyResult.index);
                      yyError  = yyResult.select(yyError);
                      if (yyResult.hasValue()) {

                        yyValue = GNode.create("ForStatement", v$g$1, v$g$2, v$g$3, v$g$4);
                        yyValue.setLocation(location(yyStart));

                        return yyResult.createValue(yyValue, yyError);
                      }
                    }
                  } else {
                    yyError = yyError.select("')' expected", yyBase);
                  }
                } // End scope for v$g$3.
              } else {
                yyError = yyError.select("';' expected", yyBase);
              }
            } // End scope for v$g$2.
          }
        } else {
          yyError = yyError.select("'(' expected", yyBase);
        }
      }
    }

    // Alternative 7.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("switch")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pCommaExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyResult = pStatement(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              yyValue = GNode.create("SwitchStatement", v$g$1, v$g$2);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Alternative <Complete>.

    yyResult = pLabel(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyResult = pStatement(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = GNode.create("LabeledStatement", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative <Incomplete>.

    if (GCC) {

      yyResult = pLabel(yyStart);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyValue = GNode.create("LabeledStatement", v$g$3, null);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 10.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("break")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(";")) {

        yyValue = GNode.create("BreakStatement", false);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      } else {
        yyError = yyError.select("';' expected", yyBase);
      }
    }

    // Alternative 11.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("continue")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(";")) {

        yyValue = GNode.create("ContinueStatement", false);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      } else {
        yyError = yyError.select("';' expected", yyBase);
      }
    }

    // Alternative 12.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("return")) {

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyResult = pCommaExpression(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$1;
      }
      { // Start scope for v$g$1.
        final Node v$g$1 = yyOpValue1;

        yyBase   = yyOption1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(";")) {

          yyValue = GNode.create("ReturnStatement", v$g$1);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("';' expected", yyBase);
        }
      } // End scope for v$g$1.
    }

    // Alternative <Direct>.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("goto")) {

      yyResult = pPrimaryIdentifier(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(";")) {

          yyValue = GNode.create("GotoStatement", null, v$g$2);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("';' expected", yyBase);
        }
      }
    }

    // Alternative <Computed>.

    if (GCC) {

      yyResult = pKeyword(yyStart);
      if (yyResult.hasValue("goto")) {

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("*")) {
          final String v$g$3 = "*";

          yyResult = pCommaExpression(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Node v$g$4 = yyResult.semanticValue();

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue(";")) {

              yyValue = GNode.create("GotoStatement", v$g$3, v$g$4);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            } else {
              yyError = yyError.select("';' expected", yyBase);
            }
          }
        } else {
          yyError = yyError.select("'*' expected", yyBase);
        }
      }
    }

    // Alternative 15.

    yyResult = pAsmKeyword(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyResult = pTypeQualifier(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$1;
      }
      { // Start scope for v$g$1.
        final Node v$g$1 = yyOpValue1;

        yyBase   = yyOption1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("(")) {

          yyResult = pAssemblyArgument(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Node v$g$2 = yyResult.semanticValue();

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue(")")) {

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(";")) {
                final String v$g$3 = ";";

                yyValue = GNode.create("AssemblyStatement", v$g$1, v$g$2, v$g$3);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              } else {
                yyError = yyError.select("';' expected", yyBase);
              }
            } else {
              yyError = yyError.select("')' expected", yyBase);
            }
          }
        } else {
          yyError = yyError.select("'(' expected", yyBase);
        }
      } // End scope for v$g$1.
    }

    // Alternative 16.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(";")) {

      yyValue = GNode.create("EmptyStatement", false);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("statement expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.Label.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLabel(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Label>.

    yyResult = pIdentifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$1 = yyResult.semanticValue();

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(":")) {

        yyOption1  = yyResult.index;
        yyOpValue1 = null;

        yyResult = pAttributeSpecifierList(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$1 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$1;
        }
        { // Start scope for v$g$2.
          final Node v$g$2 = yyOpValue1;

          yyValue = GNode.create("NamedLabel", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return new SemanticValue(yyValue, yyOption1, yyError);
        } // End scope for v$g$2.
      } else {
        yyError = yyError.select("':' expected", yyBase);
      }
    }

    // Alternative <Range>.

    if (GCC) {

      yyResult = pKeyword(yyStart);
      if (yyResult.hasValue("case")) {

        yyResult = pConditionalExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("...")) {

            yyResult = pConditionalExpression(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(":")) {

                yyValue = GNode.create("CaseLabel", v$g$1, v$g$2);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              } else {
                yyError = yyError.select("':' expected", yyBase);
              }
            }
          } else {
            yyError = yyError.select("'...' expected", yyBase);
          }
        }
      }
    }

    // Alternative <Simple>.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("case")) {

      yyResult = pConditionalExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(":")) {

          yyValue = GNode.create("CaseLabel", v$g$3);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("':' expected", yyBase);
        }
      }
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("default")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(":")) {

        yyValue = GNode.create("DefaultLabel", false);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      } else {
        yyError = yyError.select("':' expected", yyBase);
      }
    }

    // Done.
    yyError = yyError.select("label expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.CompoundStatement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pCompoundStatement(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fCompoundStatement) 
      yyColumn.chunk2.fCompoundStatement = pCompoundStatement$1(yyStart);
    return yyColumn.chunk2.fCompoundStatement;
  }

  /** Actually parse xtc.lang.c4.C4.CompoundStatement. */
  private Result pCompoundStatement$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Compound>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("{")) {

      yyResult = pPushScope(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyResult = pLocalLabelDeclarationStar(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Pair<Node> v$g$1 = yyResult.semanticValue();

          yyResult = pDeclarationOrStatementStar(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Pair<Node> v$g$2 = yyResult.semanticValue();

            yyResult = pAnnotations(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$3 = yyResult.semanticValue();

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue("}")) {

                yyResult = pPopScope(yyResult.index);
                yyError  = yyResult.select(yyError);
                if (yyResult.hasValue()) {

                  yyValue = GNode.create("CompoundStatement", v$g$1.size() + v$g$2.size() + 1).
                    addAll(v$g$1).addAll(v$g$2).add(v$g$3);
                  yyValue.setLocation(location(yyStart));

                  return yyResult.createValue(yyValue, yyError);
                }
              } else {
                yyError = yyError.select("'}' expected", yyBase);
              }
            }
          }
        }
      }
    }

    // Done.
    yyError = yyError.select("compound statement expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.LocalLabelDeclarationStar.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLocalLabelDeclarationStar(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Pair<Node> yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pLocalLabelDeclaration(yyRepetition1);
      yyError  = yyResult.select(yyError, yyRepetition1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }
    { // Start scope for yyValue.
      yyValue = yyRepValue1.reverse();

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    } // End scope for yyValue.
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.LocalLabelDeclaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLocalLabelDeclaration(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fLocalLabelDeclaration) 
      yyColumn.chunk2.fLocalLabelDeclaration = pLocalLabelDeclaration$1(yyStart);
    return yyColumn.chunk2.fLocalLabelDeclaration;
  }

  /** Actually parse xtc.lang.c4.C4.LocalLabelDeclaration. */
  private Result pLocalLabelDeclaration$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__label__")) {

      yyResult = pIdentifier(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final String v$g$1 = yyResult.semanticValue();

        yyResult = pLocalLabelDeclaration$$Star1(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Pair<String> v$g$2 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(";")) {

            yyValue = GNode.createFromPair("LocalLabelDeclaration", v$g$1, v$g$2);
            yyValue.setLocation(location(yyStart));

            return yyResult.createValue(yyValue, yyError);
          } else {
            yyError = yyError.select("';' expected", yyBase);
          }
        }
      }
    }

    // Done.
    yyError = yyError.select("local label declaration expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.LocalLabelDeclaration$$Star1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLocalLabelDeclaration$$Star1(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fLocalLabelDeclaration$$Star1) 
      yyColumn.chunk2.fLocalLabelDeclaration$$Star1 = pLocalLabelDeclaration$$Star1$1(yyStart);
    return yyColumn.chunk2.fLocalLabelDeclaration$$Star1;
  }

  /** Actually parse xtc.lang.c4.C4.LocalLabelDeclaration$$Star1. */
  private Result pLocalLabelDeclaration$$Star1$1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Pair<String> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(",")) {

      yyResult = pIdentifier(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final String v$el$1 = yyResult.semanticValue();

        yyResult = pLocalLabelDeclaration$$Star1(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Pair<String> v$2 = yyResult.semanticValue();

          yyValue = new Pair<String>(v$el$1, v$2);

          return yyResult.createValue(yyValue, yyError);
        }
      }
    }

    // Alternative 2.

    yyValue = Pair.empty();

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DeclarationOrStatementStar.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationOrStatementStar(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Pair<Node> yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pDeclarationOrStatement(yyRepetition1);
      yyError  = yyResult.select(yyError, yyRepetition1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }
    { // Start scope for yyValue.
      yyValue = yyRepValue1.reverse();

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    } // End scope for yyValue.
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DeclarationOrStatement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationOrStatement(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk2) yyColumn.chunk2 = new Chunk2();
    if (null == yyColumn.chunk2.fDeclarationOrStatement) 
      yyColumn.chunk2.fDeclarationOrStatement = pDeclarationOrStatement$1(yyStart);
    return yyColumn.chunk2.fDeclarationOrStatement;
  }

  /** Actually parse xtc.lang.c4.C4.DeclarationOrStatement. */
  private Result pDeclarationOrStatement$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative <Declaration>.

    yyState.mark();

    yyResult = pDeclaration(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node d = yyResult.semanticValue();

      yyValue = yyState.annotate(d);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Statement>.

    yyResult = pStatement(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node s = yyResult.semanticValue();

      yyValue = yyState.annotate(s);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.InitialClause.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pInitialClause(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative <Declaration>.

    yyResult = pDeclaration(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      // Commit the state modification.
      yyState.commit();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Expression>.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyResult = pCommaExpression(yyOption1);
    yyError  = yyResult.select(yyError, yyOption1);
    if (yyResult.hasValue()) {
      final Node v$el$3 = yyResult.semanticValue();

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$3;
    }
    { // Start scope for yyValue.
      yyValue = yyOpValue1;

      yyBase   = yyOption1;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(";")) {

        // Commit the state modification.
        yyState.commit();

        return yyResult.createValue(yyValue, yyError);
      } else {
        yyError = yyError.select("';' expected", yyBase);
      }
    } // End scope for yyValue.

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.CommaExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pCommaExpression(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fCommaExpression) 
      yyColumn.chunk3.fCommaExpression = pCommaExpression$1(yyStart);
    return yyColumn.chunk3.fCommaExpression;
  }

  /** Actually parse xtc.lang.c4.C4.CommaExpression. */
  private Result pCommaExpression$1(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pAssignmentExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pCommaExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$3 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$3, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$4.
        final Pair<Action<Node>> v$4 = yyRepValue1.reverse();

        yyValue = apply(v$4, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$4.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.CommaExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pCommaExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Comma>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(",")) {

      yyResult = pAssignmentExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("CommaExpression", v$1, v$g$2);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("comma expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AssignmentExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAssignmentExpression(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fAssignmentExpression) 
      yyColumn.chunk3.fAssignmentExpression = pAssignmentExpression$1(yyStart);
    return yyColumn.chunk3.fAssignmentExpression;
  }

  /** Actually parse xtc.lang.c4.C4.AssignmentExpression. */
  private Result pAssignmentExpression$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Assignment>.

    yyResult = pUnaryExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyResult = pAssignmentOperator(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final String v$g$2 = yyResult.semanticValue();

        yyResult = pAssignmentExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$3 = yyResult.semanticValue();

          yyValue = GNode.create("AssignmentExpression", v$g$1, v$g$2, v$g$3);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        }
      }
    }

    // Alternative <Base>.

    yyResult = pConditionalExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AssignmentOperator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAssignmentOperator(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Equal>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("=")) {
      yyValue = "=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <PlusEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("+=")) {
      yyValue = "+=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <MinusEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("-=")) {
      yyValue = "-=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <TimesEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("*=")) {
      yyValue = "*=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <OverEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("/=")) {
      yyValue = "/=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <ModuloEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("%=")) {
      yyValue = "%=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <LeftEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("<<=")) {
      yyValue = "<<=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <RightEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(">>=")) {
      yyValue = ">>=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <AndEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("&=")) {
      yyValue = "&=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <XorEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("^=")) {
      yyValue = "^=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <OrEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("|=")) {
      yyValue = "|=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("assignment operator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ConditionalExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pConditionalExpression(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fConditionalExpression) 
      yyColumn.chunk3.fConditionalExpression = pConditionalExpression$1(yyStart);
    return yyColumn.chunk3.fConditionalExpression;
  }

  /** Actually parse xtc.lang.c4.C4.ConditionalExpression. */
  private Result pConditionalExpression$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Conditional>.

    yyResult = pLogicalOrExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("?")) {

        yyResult = pCommaExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$2 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(":")) {

            yyResult = pConditionalExpression(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$3 = yyResult.semanticValue();

              yyValue = GNode.create("ConditionalExpression", v$g$1, v$g$2, v$g$3);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            }
          } else {
            yyError = yyError.select("':' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'?' expected", yyBase);
      }
    }

    // Alternative <IncompleteConditional>.

    if (GCC) {

      yyResult = pLogicalOrExpression(yyStart);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$4 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("?")) {

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(":")) {

            yyResult = pConditionalExpression(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$6 = yyResult.semanticValue();

              yyValue = GNode.create("ConditionalExpression", v$g$4, null, v$g$6);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            }
          } else {
            yyError = yyError.select("':' expected", yyBase);
          }
        } else {
          yyError = yyError.select("'?' expected", yyBase);
        }
      }
    }

    // Alternative <Base>.

    yyResult = pLogicalOrExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("conditional expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.LogicalOrExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLogicalOrExpression(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fLogicalOrExpression) 
      yyColumn.chunk3.fLogicalOrExpression = pLogicalOrExpression$1(yyStart);
    return yyColumn.chunk3.fLogicalOrExpression;
  }

  /** Actually parse xtc.lang.c4.C4.LogicalOrExpression. */
  private Result pLogicalOrExpression$1(final int yyStart) 
    throws IOException {

    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pLogicalAndExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pLogicalOrExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$3 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$3, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$4.
        final Pair<Action<Node>> v$4 = yyRepValue1.reverse();

        yyValue = apply(v$4, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$4.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.LogicalOrExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLogicalOrExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Or>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("||")) {

      yyResult = pLogicalAndExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("LogicalOrExpression", v$1, v$g$2);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("logical or expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.LogicalAndExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLogicalAndExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pBitwiseOrExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pLogicalAndExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$3 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$3, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$4.
        final Pair<Action<Node>> v$4 = yyRepValue1.reverse();

        yyValue = apply(v$4, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$4.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.LogicalAndExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLogicalAndExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <And>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("&&")) {

      yyResult = pBitwiseOrExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("LogicalAndExpression", v$1, v$g$2);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("logical and expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.BitwiseOrExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBitwiseOrExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pBitwiseXorExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pBitwiseOrExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$3 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$3, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$4.
        final Pair<Action<Node>> v$4 = yyRepValue1.reverse();

        yyValue = apply(v$4, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$4.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.BitwiseOrExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBitwiseOrExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Or>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("|")) {

      yyResult = pBitwiseXorExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("BitwiseOrExpression", v$1, v$g$2);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("bitwise or expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.BitwiseXorExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBitwiseXorExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pBitwiseAndExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pBitwiseXorExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$3 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$3, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$4.
        final Pair<Action<Node>> v$4 = yyRepValue1.reverse();

        yyValue = apply(v$4, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$4.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.BitwiseXorExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBitwiseXorExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Xor>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("^")) {

      yyResult = pBitwiseAndExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("BitwiseXorExpression", v$1, v$g$2);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("bitwise xor expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.BitwiseAndExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBitwiseAndExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pEqualityExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pBitwiseAndExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$3 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$3, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$4.
        final Pair<Action<Node>> v$4 = yyRepValue1.reverse();

        yyValue = apply(v$4, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$4.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.BitwiseAndExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBitwiseAndExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <And>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("&")) {

      yyResult = pEqualityExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("BitwiseAndExpression", v$1, v$g$2);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("bitwise and expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.EqualityExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEqualityExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pRelationalExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pEqualityExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$4 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$4, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$5.
        final Pair<Action<Node>> v$5 = yyRepValue1.reverse();

        yyValue = apply(v$5, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$5.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.EqualityExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEqualityExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Recursion>.

    yyResult = pEqualityOperator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$2 = yyResult.semanticValue();

      yyResult = pRelationalExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("EqualityExpression", v$1, v$g$2, v$g$3);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.EqualityOperator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEqualityOperator(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Equal>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("==")) {
      yyValue = "==";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <NotEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("!=")) {
      yyValue = "!=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("equality operator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.RelationalExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pRelationalExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pShiftExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pRelationalExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$4 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$4, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$5.
        final Pair<Action<Node>> v$5 = yyRepValue1.reverse();

        yyValue = apply(v$5, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$5.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.RelationalExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pRelationalExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Recursion>.

    yyResult = pRelationalOperator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$2 = yyResult.semanticValue();

      yyResult = pShiftExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("RelationalExpression", v$1, v$g$2, v$g$3);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.RelationalOperator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pRelationalOperator(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <LessEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("<=")) {
      yyValue = "<=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Less>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("<")) {
      yyValue = "<";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <GreaterEqual>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(">=")) {
      yyValue = ">=";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Greater>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(">")) {
      yyValue = ">";

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("relational operator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ShiftExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pShiftExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pAdditiveExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pShiftExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$4 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$4, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$5.
        final Pair<Action<Node>> v$5 = yyRepValue1.reverse();

        yyValue = apply(v$5, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$5.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.ShiftExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pShiftExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Recursion>.

    yyResult = pShiftOperator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$2 = yyResult.semanticValue();

      yyResult = pAdditiveExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("ShiftExpression", v$1, v$g$2, v$g$3);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ShiftOperator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pShiftOperator(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Left>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("<<")) {
      yyValue = "<<";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Right>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(">>")) {
      yyValue = ">>";

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("shift operator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AdditiveExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAdditiveExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pMultiplicativeExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pAdditiveExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$4 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$4, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$5.
        final Pair<Action<Node>> v$5 = yyRepValue1.reverse();

        yyValue = apply(v$5, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$5.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.AdditiveExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAdditiveExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Recursion>.

    yyResult = pAdditiveOperator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$2 = yyResult.semanticValue();

      yyResult = pMultiplicativeExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("AdditiveExpression", v$1, v$g$2, v$g$3);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AdditiveOperator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAdditiveOperator(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Plus>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("+")) {
      yyValue = "+";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Minus>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("-")) {
      yyValue = "-";

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("additive operator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.MultiplicativeExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pMultiplicativeExpression(final int yyStart) 
    throws IOException {

    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Base>.

    yyResult = pCastExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pMultiplicativeExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$4 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$4, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$5.
        final Pair<Action<Node>> v$5 = yyRepValue1.reverse();

        yyValue = apply(v$5, yyValue, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$5.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal 
   * xtc.lang.c4.C4.MultiplicativeExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pMultiplicativeExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative <Recursion>.

    yyResult = pMultiplicativeOperator(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$2 = yyResult.semanticValue();

      yyResult = pCastExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("MultiplicativeExpression", v$1, v$g$2, v$g$3);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.MultiplicativeOperator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pMultiplicativeOperator(final int yyStart) 
    throws IOException {

    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Times>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("*")) {
      yyValue = "*";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Over>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("/")) {
      yyValue = "/";

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Modulo>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("%")) {
      yyValue = "%";

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("multiplicative operator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.CastExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pCastExpression(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fCastExpression) 
      yyColumn.chunk3.fCastExpression = pCastExpression$1(yyStart);
    return yyColumn.chunk3.fCastExpression;
  }

  /** Actually parse xtc.lang.c4.C4.CastExpression. */
  private Result pCastExpression$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Cast>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("(")) {

      yyResult = pTypeName(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(")")) {

          yyResult = pCastExpression(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Node v$g$2 = yyResult.semanticValue();

            yyValue = GNode.create("CastExpression", v$g$1, v$g$2);
            yyValue.setLocation(location(yyStart));

            return yyResult.createValue(yyValue, yyError);
          }
        } else {
          yyError = yyError.select("')' expected", yyBase);
        }
      }
    }

    // Alternative <Base>.

    yyResult = pUnaryExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("cast expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.UnaryExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pUnaryExpression(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fUnaryExpression) 
      yyColumn.chunk3.fUnaryExpression = pUnaryExpression$1(yyStart);
    return yyColumn.chunk3.fUnaryExpression;
  }

  /** Actually parse xtc.lang.c4.C4.UnaryExpression. */
  private Result pUnaryExpression$1(final int yyStart) throws IOException {
    Result     yyResult;
    Result     yyPredResult;
    boolean    yyPredMatched;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("sizeof")) {

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyBase   = yyChoice1;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pTypeName(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyPredMatched = false;

            yyPredResult = pSymbol(yyResult.index);
            if (yyPredResult.hasValue("{")) {

              yyPredMatched = true;
            }

            if (! yyPredMatched) {

              yyValue = GNode.create("SizeofExpression", v$g$1);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            } else {
              yyError = yyError.select("unary expression expected", yyStart);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }

      // Nested alternative 2.

      yyResult = pUnaryExpression(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = GNode.create("SizeofExpression", v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 2.

    yyResult = pAlignofKeyword(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyBase   = yyChoice1;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pTypeName(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyPredMatched = false;

            yyPredResult = pSymbol(yyResult.index);
            if (yyPredResult.hasValue("{")) {

              yyPredMatched = true;
            }

            if (! yyPredMatched) {

              yyValue = GNode.create("AlignofExpression", v$g$1);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            } else {
              yyError = yyError.select("unary expression expected", yyStart);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }

      // Nested alternative 2.

      yyResult = pUnaryExpression(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = GNode.create("AlignofExpression", v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__builtin_offsetof")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pTypeName(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(",")) {

            yyResult = pPostfixExpression(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(")")) {

                yyValue = GNode.create("OffsetofExpression", v$g$1, v$g$2);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              } else {
                yyError = yyError.select("')' expected", yyBase);
              }
            }
          } else {
            yyError = yyError.select("',' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__builtin_types_compatible_p")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pTypeName(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(",")) {

            yyResult = pTypeName(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(")")) {

                yyValue = GNode.create("TypeCompatibilityExpression", v$g$1, v$g$2);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              } else {
                yyError = yyError.select("')' expected", yyBase);
              }
            }
          } else {
            yyError = yyError.select("',' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Alternative 5.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("-")) {

      yyResult = pCastExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyValue = GNode.create("UnaryMinusExpression", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 6.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("+")) {

      yyResult = pCastExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyValue = GNode.create("UnaryPlusExpression", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 7.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("!")) {

      yyResult = pCastExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyValue = GNode.create("LogicalNegationExpression", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 8.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("~")) {

      yyResult = pCastExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyValue = GNode.create("BitwiseNegationExpression", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 9.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("&")) {

      yyResult = pCastExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyValue = GNode.create("AddressExpression", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative <LabelAddress>.

    if (GCC) {

      yyResult = pSymbol(yyStart);
      if (yyResult.hasValue("&&")) {

        yyResult = pIdentifier(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String v$g$1 = yyResult.semanticValue();

          yyValue = GNode.create("LabelAddressExpression", v$g$1);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        }
      }
    }

    // Alternative 11.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("*")) {

      yyResult = pCastExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyValue = GNode.create("IndirectionExpression", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 12.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("++")) {

      yyResult = pUnaryExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyValue = GNode.create("PreincrementExpression", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 13.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("--")) {

      yyResult = pUnaryExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyValue = GNode.create("PredecrementExpression", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative <Extension>.

    if (GCC) {

      yyResult = pKeyword(yyStart);
      if (yyResult.hasValue("__extension__")) {

        yyResult = pCastExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyValue = GNode.create("ExtensionExpression", v$g$1);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        }
      }
    }

    // Alternative <Base>.

    yyResult = pPostfixExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("unary expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AlignofKeyword.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAlignofKeyword(final int yyStart) throws IOException {
    Result     yyResult;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__alignof__")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__alignof")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("alignof keyword expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.PostfixExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPostfixExpression(final int yyStart) throws IOException {
    Result             yyResult;
    int                yyRepetition1;
    Pair<Action<Node>> yyRepValue1;
    Node               yyValue;
    ParseError         yyError = ParseError.DUMMY;

    // Alternative <Compound>.

    yyResult = pCompoundLiteral(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$6 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pPostfixExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$7 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$7, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$8.
        final Pair<Action<Node>> v$8 = yyRepValue1.reverse();

        yyValue = apply(v$8, v$g$6, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$8.
    }

    // Alternative <Primary>.

    yyResult = pPrimaryExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$9 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyResult = pPostfixExpression$$Tail1(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {
          final Action<Node> v$10 = yyResult.semanticValue();

          yyRepetition1 = yyResult.index;
          yyRepValue1   = new Pair<Action<Node>>(v$10, yyRepValue1);
          continue;
        }
        break;
      }
      { // Start scope for v$11.
        final Pair<Action<Node>> v$11 = yyRepValue1.reverse();

        yyValue = apply(v$11, v$g$9, yyStart);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$11.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.PostfixExpression$$Tail1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPostfixExpression$$Tail1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    int          yyBase;
    int          yyOption1;
    Node         yyOpValue1;
    Action<Node> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("[")) {

      yyResult = pCommaExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("]")) {

          yyValue = new Action<Node>() {
            public Node run(Node v$1) {
              return GNode.create("SubscriptExpression", v$1, v$g$2);
            }};

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("']' expected", yyBase);
        }
      }
    }

    // Alternative 2.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(".")) {

      yyResult = pIdentifier(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final String v$g$3 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("DirectComponentSelection", v$1, v$g$3);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 3.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("->")) {

      yyResult = pIdentifier(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final String v$g$4 = yyResult.semanticValue();

        yyValue = new Action<Node>() {
          public Node run(Node v$1) {
            return GNode.create("IndirectComponentSelection", v$1, v$g$4);
          }};

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 4.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("(")) {

      yyOption1  = yyResult.index;
      yyOpValue1 = null;

      yyResult = pExpressionList(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$1;
      }
      { // Start scope for v$g$5.
        final Node v$g$5 = yyOpValue1;

        yyBase   = yyOption1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(")")) {

          yyValue = new Action<Node>() {
            public Node run(Node v$1) {
              return GNode.create("FunctionCall", v$1, v$g$5);
            }};

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("')' expected", yyBase);
        }
      } // End scope for v$g$5.
    }

    // Alternative 5.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("++")) {

      yyValue = new Action<Node>() {
        public Node run(Node v$1) {
          return GNode.create("PostincrementExpression", v$1);
        }};

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 6.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("--")) {

      yyValue = new Action<Node>() {
        public Node run(Node v$1) {
          return GNode.create("PostdecrementExpression", v$1);
        }};

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("postfix expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.ExpressionList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pExpressionList(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fExpressionList) 
      yyColumn.chunk3.fExpressionList = pExpressionList$1(yyStart);
    return yyColumn.chunk3.fExpressionList;
  }

  /** Actually parse xtc.lang.c4.C4.ExpressionList. */
  private Result pExpressionList$1(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Expressions>.

    yyResult = pAssignmentExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyResult = pExpressionList$$Star1(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Pair<Node> v$g$2 = yyResult.semanticValue();

        yyValue = GNode.createFromPair("ExpressionList", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.ExpressionList$$Star1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pExpressionList$$Star1(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fExpressionList$$Star1) 
      yyColumn.chunk3.fExpressionList$$Star1 = pExpressionList$$Star1$1(yyStart);
    return yyColumn.chunk3.fExpressionList$$Star1;
  }

  /** Actually parse xtc.lang.c4.C4.ExpressionList$$Star1. */
  private Result pExpressionList$$Star1$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Pair<Node> yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(",")) {

      yyResult = pAssignmentExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyResult = pExpressionList$$Star1(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Pair<Node> v$2 = yyResult.semanticValue();

          yyValue = new Pair<Node>(v$el$1, v$2);

          return yyResult.createValue(yyValue, yyError);
        }
      }
    }

    // Alternative 2.

    yyValue = Pair.empty();

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.CompoundLiteral.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pCompoundLiteral(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("(")) {

      yyResult = pTypeName(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$1 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(")")) {

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue("{")) {

            yyResult = pInitializerList(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              yyOption1  = yyResult.index;

              yyBase   = yyOption1;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(",")) {

                yyOption1  = yyResult.index;
              } else {
                yyError = yyError.select("',' expected", yyBase);
              }

              yyBase   = yyOption1;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue("}")) {

                yyValue = GNode.create("CompoundLiteral", v$g$1, v$g$2);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              } else {
                yyError = yyError.select("'}' expected", yyBase);
              }
            }
          } else {
            yyError = yyError.select("'{' expected", yyBase);
          }
        } else {
          yyError = yyError.select("')' expected", yyBase);
        }
      }
    }

    // Done.
    yyError = yyError.select("compound literal expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.PrimaryExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPrimaryExpression(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Constant>.

    yyResult = pConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pIdentifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$1 = yyResult.semanticValue();

      yyValue = GNode.create("PrimaryIdentifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    if (GCC) {

      yyResult = pSymbol(yyStart);
      if (yyResult.hasValue("(")) {

        yyResult = pCompoundStatement(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyValue = GNode.create("StatementAsExpression", v$g$1);
            yyValue.setLocation(location(yyStart));

            return yyResult.createValue(yyValue, yyError);
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      }
    }

    // Alternative 4.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__builtin_va_arg")) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pAssignmentExpression(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(",")) {

            yyResult = pTypeName(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$2 = yyResult.semanticValue();

              yyBase   = yyResult.index;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(")")) {

                yyValue = GNode.create("VariableArgumentAccess", v$g$1, v$g$2);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              } else {
                yyError = yyError.select("')' expected", yyBase);
              }
            }
          } else {
            yyError = yyError.select("',' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Alternative <ParenthesizedExpression>.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("(")) {

      yyResult = pCommaExpression(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        yyValue = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(")")) {

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("')' expected", yyBase);
        }
      }
    }

    // Done.
    yyError = yyError.select("primary expression expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.PrimaryIdentifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPrimaryIdentifier(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pIdentifier(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$1 = yyResult.semanticValue();

      yyValue = GNode.create("PrimaryIdentifier", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AssemblyDefinition.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAssemblyDefinition(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSimpleAssemblyExpression(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(";")) {

        yyValue = GNode.create("AssemblyDefinition", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      } else {
        yyError = yyError.select("';' expected", yyBase);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.SimpleAssemblyExpression.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSimpleAssemblyExpression(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fSimpleAssemblyExpression) 
      yyColumn.chunk3.fSimpleAssemblyExpression = pSimpleAssemblyExpression$1(yyStart);
    return yyColumn.chunk3.fSimpleAssemblyExpression;
  }

  /** Actually parse xtc.lang.c4.C4.SimpleAssemblyExpression. */
  private Result pSimpleAssemblyExpression$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pAsmKeyword(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pStringConstant(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$1 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyValue = GNode.create("SimpleAssemblyExpression", v$g$1);
            yyValue.setLocation(location(yyStart));

            return yyResult.createValue(yyValue, yyError);
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AssemblyArgument.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAssemblyArgument(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Node       yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pStringConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyBase   = yyChoice1;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue(":")) {

        yyOption1  = yyResult.index;
        yyOpValue1 = null;

        yyResult = pAssemblyOperands(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {
          final Node v$el$1 = yyResult.semanticValue();

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$1;
        }
        { // Start scope for v$g$2.
          final Node v$g$2 = yyOpValue1;

          final int yyChoice2 = yyOption1;

          // Nested alternative 1.

          yyBase   = yyChoice2;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(":")) {

            yyOption1  = yyResult.index;
            yyOpValue1 = null;

            yyResult = pAssemblyOperands(yyOption1);
            yyError  = yyResult.select(yyError, yyOption1);
            if (yyResult.hasValue()) {
              final Node v$el$2 = yyResult.semanticValue();

              yyOption1  = yyResult.index;
              yyOpValue1 = v$el$2;
            }
            { // Start scope for v$g$3.
              final Node v$g$3 = yyOpValue1;

              final int yyChoice3 = yyOption1;

              // Nested alternative 1.

              yyBase   = yyChoice3;
              yyResult = pSymbol(yyBase);
              if (yyResult.hasValue(":")) {

                yyResult = pAssemblyClobbers(yyResult.index);
                yyError  = yyResult.select(yyError);
                if (yyResult.hasValue()) {
                  final Node v$g$4 = yyResult.semanticValue();

                  yyValue = GNode.create("AssemblyArgument", v$g$1, v$g$2, v$g$3, v$g$4);
                  yyValue.setLocation(location(yyStart));

                  return yyResult.createValue(yyValue, yyError);
                }
              } else {
                yyError = yyError.select("':' expected", yyBase);
              }

              // Nested alternative 2.

              yyValue = GNode.create("AssemblyArgument", v$g$1, v$g$2, v$g$3);
              yyValue.setLocation(location(yyStart));

              return new SemanticValue(yyValue, yyChoice3, yyError);
            } // End scope for v$g$3.
          } else {
            yyError = yyError.select("':' expected", yyBase);
          }

          // Nested alternative 2.

          yyValue = GNode.create("AssemblyArgument", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return new SemanticValue(yyValue, yyChoice2, yyError);
        } // End scope for v$g$2.
      } else {
        yyError = yyError.select("':' expected", yyBase);
      }

      // Nested alternative 2.

      yyValue = GNode.create("AssemblyArgument", v$g$1);
      yyValue.setLocation(location(yyStart));

      return new SemanticValue(yyValue, yyChoice1, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AssemblyOperands.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAssemblyOperands(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk3) yyColumn.chunk3 = new Chunk3();
    if (null == yyColumn.chunk3.fAssemblyOperands) 
      yyColumn.chunk3.fAssemblyOperands = pAssemblyOperands$1(yyStart);
    return yyColumn.chunk3.fAssemblyOperands;
  }

  /** Actually parse xtc.lang.c4.C4.AssemblyOperands. */
  private Result pAssemblyOperands$1(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pAssemblyOperand(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyResult = pAssemblyOperands$$Star1(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Pair<Node> v$g$2 = yyResult.semanticValue();

        yyValue = GNode.createFromPair("AssemblyOperands", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.AssemblyOperands$$Star1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAssemblyOperands$$Star1(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fAssemblyOperands$$Star1) 
      yyColumn.chunk4.fAssemblyOperands$$Star1 = pAssemblyOperands$$Star1$1(yyStart);
    return yyColumn.chunk4.fAssemblyOperands$$Star1;
  }

  /** Actually parse xtc.lang.c4.C4.AssemblyOperands$$Star1. */
  private Result pAssemblyOperands$$Star1$1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Pair<Node> yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue(",")) {

      yyResult = pAssemblyOperand(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyResult = pAssemblyOperands$$Star1(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Pair<Node> v$2 = yyResult.semanticValue();

          yyValue = new Pair<Node>(v$el$1, v$2);

          return yyResult.createValue(yyValue, yyError);
        }
      }
    }

    // Alternative 2.

    yyValue = Pair.empty();

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AssemblyOperand.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAssemblyOperand(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fAssemblyOperand) 
      yyColumn.chunk4.fAssemblyOperand = pAssemblyOperand$1(yyStart);
    return yyColumn.chunk4.fAssemblyOperand;
  }

  /** Actually parse xtc.lang.c4.C4.AssemblyOperand. */
  private Result pAssemblyOperand$1(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    String     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyBase   = yyOption1;
    yyResult = pSymbol(yyBase);
    if (yyResult.hasValue("[")) {

      yyResult = pWord(yyResult.index);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final String v$el$1 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("]")) {

          yyOption1  = yyResult.index;
          yyOpValue1 = v$el$1;
        } else {
          yyError = yyError.select("']' expected", yyBase);
        }
      }
    } else {
      yyError = yyError.select("'[' expected", yyBase);
    }
    { // Start scope for v$g$1.
      final String v$g$1 = yyOpValue1;

      yyResult = pStringConstant(yyOption1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue("(")) {

          yyResult = pCommaExpression(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Node v$g$3 = yyResult.semanticValue();

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue(")")) {

              yyValue = GNode.create("AssemblyOperand", v$g$1, v$g$2, v$g$3);
              yyValue.setLocation(location(yyStart));

              return yyResult.createValue(yyValue, yyError);
            } else {
              yyError = yyError.select("')' expected", yyBase);
            }
          }
        } else {
          yyError = yyError.select("'(' expected", yyBase);
        }
      }
    } // End scope for v$g$1.

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AssemblyClobbers.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAssemblyClobbers(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pStringConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node v$g$1 = yyResult.semanticValue();

      yyRepetition1 = yyResult.index;
      yyRepValue1   = Pair.empty();
      while (true) {

        yyBase   = yyRepetition1;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(",")) {

          yyResult = pStringConstant(yyResult.index);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
            continue;
          }
        } else {
          yyError = yyError.select("',' expected", yyBase);
        }
        break;
      }
      { // Start scope for v$g$2.
        final Pair<Node> v$g$2 = yyRepValue1.reverse();

        yyValue = GNode.createFromPair("AssemblyClobbers", v$g$1, v$g$2);
        yyValue.setLocation(location(yyStart));

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      } // End scope for v$g$2.
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AsmKeyword.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAsmKeyword(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fAsmKeyword) 
      yyColumn.chunk4.fAsmKeyword = pAsmKeyword$1(yyStart);
    return yyColumn.chunk4.fAsmKeyword;
  }

  /** Actually parse xtc.lang.c4.C4.AsmKeyword. */
  private Result pAsmKeyword$1(final int yyStart) throws IOException {
    Result     yyResult;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("asm")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__asm")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 3.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("__asm__")) {

      yyValue = null;

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    yyError = yyError.select("asm keyword expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.DeclarationOrFunctionDefinition.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDeclarationOrFunctionDefinition(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative 1.

    yyState.mark();

    yyResult = pDeclaration(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node d = yyResult.semanticValue();

      yyValue = yyState.annotate(d);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 2.

    yyResult = pFunctionDefinition(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node fd = yyResult.semanticValue();

      yyValue = yyState.annotate(fd);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.GlobalIntroductionAdvice.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  public Result pGlobalIntroductionAdvice(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("advice_intro")) {
      final String v$g$1 = "advice_intro";

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pIdentifier(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String aName = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue("{")) {

              yyResult = pPushScope(yyResult.index);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {

                yyState.setAdvice(aName);

                yyRepetition1 = yyResult.index;
                yyRepValue1   = Pair.empty();
                while (true) {

                  yyResult = pDeclarationOrFunctionDefinition(yyRepetition1);
                  yyError  = yyResult.select(yyError, yyRepetition1);
                  if (yyResult.hasValue()) {
                    final Node v$el$1 = yyResult.semanticValue();

                    yyRepetition1 = yyResult.index;
                    yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
                    continue;
                  }
                  break;
                }
                { // Start scope for v$g$2.
                  final Pair<Node> v$g$2 = yyRepValue1.reverse();

                  yyBase   = yyRepetition1;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyBase   = yyResult.index;
                    yyResult = pSymbol(yyBase);
                    if (yyResult.hasValue(";")) {

                      yyResult = pPopScope(yyResult.index);
                      yyError  = yyResult.select(yyError);
                      if (yyResult.hasValue()) {

                        yyValue = GNode.create("GlobalIntroductionAdvice", v$g$2.size() + 2).
                          add(v$g$1).add(aName).addAll(v$g$2);
                        yyValue.setLocation(location(yyStart));

                        return yyResult.createValue(yyValue, yyError);
                      }
                    } else {
                      yyError = yyError.select("';' expected", yyBase);
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                } // End scope for v$g$2.
              }
            } else {
              yyError = yyError.select("'{' expected", yyBase);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Done.
    yyError = yyError.select("global introduction advice expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AspectStructureDeclarationList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAspectStructureDeclarationList(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Regular>.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pAnnotatedAspectStructureDeclaration(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepeated1   = true;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }

    if (yyRepeated1) {
      final Pair<Node> v$g$1 = yyRepValue1.reverse();

      yyResult = pAnnotations(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyValue = GNode.create("AspectStructureDeclarationList", v$g$1.size() + 1).
          addAll(v$g$1).add(v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative <Empty>.

    if (GCC) {

      yyResult = pAnnotations(yyStart);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyValue = GNode.create("AspectStructureDeclarationList", v$g$3);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("aspect structure declaration list expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AnnotatedAspectStructureDeclaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAnnotatedAspectStructureDeclaration(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Start a state modification.
    yyState.start();

    // Alternative 1.

    yyState.mark();

    yyResult = pAspectStructureDeclaration(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node d = yyResult.semanticValue();

      yyValue = yyState.annotate(d);

      // Commit the state modification.
      yyState.commit();

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Abort the state modification.
    yyState.abort();

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AspectStructureDeclaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAspectStructureDeclaration(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    boolean    yyRepeated1;
    int        yyOption1;
    String     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyBase   = yyOption1;
    yyResult = pKeyword(yyBase);
    if (yyResult.hasValue("__extension__")) {
      final String v$el$1 = "__extension__";

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    } else {
      yyError = yyError.select("'__extension__' expected", yyBase);
    }
    { // Start scope for v$g$1.
      final String v$g$1 = yyOpValue1;

      final int yyChoice1 = yyOption1;

      // Nested alternative 1.

      yyResult = pStructureAdviceDeclaration(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$2 = yyResult.semanticValue();

        yyBase   = yyResult.index;
        yyResult = pSymbol(yyBase);
        if (yyResult.hasValue(";")) {

          yyValue = GNode.create("AspectStructureDeclaration", v$g$1, v$g$2);
          yyValue.setLocation(location(yyStart));

          return yyResult.createValue(yyValue, yyError);
        } else {
          yyError = yyError.select("';' expected", yyBase);
        }
      }

      // Nested alternative 2.

      yyResult = pSpecifierQualifierList(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Node v$g$3 = yyResult.semanticValue();

        yyResult = pOptionalStructureDeclaratorList(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$4 = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(";")) {

            yyOption1  = yyResult.index;

            if (GCC) {

              yyRepetition1 = yyOption1;
              yyRepeated1   = false;
              while (true) {

                yyBase   = yyRepetition1;
                yyResult = pSymbol(yyBase);
                if (yyResult.hasValue(";")) {

                  yyRepetition1 = yyResult.index;
                  yyRepeated1   = true;
                  continue;
                } else {
                  yyError = yyError.select("';' expected", yyBase);
                }
                break;
              }

              if (yyRepeated1) {

                yyOption1  = yyRepetition1;
              }
            }

            yyValue = GNode.create("AspectStructureDeclaration", v$g$1, v$g$3, v$g$4);
            yyValue.setLocation(location(yyStart));

            return new SemanticValue(yyValue, yyOption1, yyError);
          } else {
            yyError = yyError.select("';' expected", yyBase);
          }
        }
      }
    } // End scope for v$g$1.

    // Done.
    yyError = yyError.select("aspect structure declaration expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.StructureAdviceDeclaration.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStructureAdviceDeclaration(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("advice_intro")) {
      final String v$g$1 = "advice_intro";

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pIdentifier(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String aName = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue("{")) {

              yyResult = pPushScope(yyResult.index);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {

                yyState.setAdvice(aName);

                yyResult = pAspectStructureDeclarationList(yyResult.index);
                yyError  = yyResult.select(yyError);
                if (yyResult.hasValue()) {
                  final Node v$g$2 = yyResult.semanticValue();

                  yyBase   = yyResult.index;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyResult = pPopScope(yyResult.index);
                    yyError  = yyResult.select(yyError);
                    if (yyResult.hasValue()) {

                      yyValue = GNode.create("StructureAdviceDeclaration", v$g$1, aName, v$g$2);
                      yyValue.setLocation(location(yyStart));

                      return yyResult.createValue(yyValue, yyError);
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                }
              }
            } else {
              yyError = yyError.select("'{' expected", yyBase);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Done.
    yyError = yyError.select("structure advice declaration expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AspectFunctionDefinition.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAspectFunctionDefinition(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyOption1;
    Object     yyOpValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyOption1  = yyStart;
    yyOpValue1 = null;

    yyBase   = yyOption1;
    yyResult = pKeyword(yyBase);
    if (yyResult.hasValue("__extension__")) {
      final String v$el$1 = "__extension__";

      yyOption1  = yyResult.index;
      yyOpValue1 = v$el$1;
    } else {
      yyError = yyError.select("'__extension__' expected", yyBase);
    }
    { // Start scope for v$g$1.
      final String v$g$1 = cast(yyOpValue1);

      yyOpValue1 = null;

      yyResult = pDeclarationSpecifiers(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {
        final Node v$el$2 = yyResult.semanticValue();

        yyOption1  = yyResult.index;
        yyOpValue1 = v$el$2;
      }
      { // Start scope for v$g$2.
        final Node v$g$2 = cast(yyOpValue1);

        yyResult = pDeclarator(yyOption1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final Node v$g$3 = yyResult.semanticValue();

          yyResult = pFunctionDeclaratorContext(yyResult.index);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {

            yyOption1  = yyResult.index;
            yyOpValue1 = null;

            yyResult = pDeclarationList(yyOption1);
            yyError  = yyResult.select(yyError, yyOption1);
            if (yyResult.hasValue()) {
              final Node v$el$3 = yyResult.semanticValue();

              yyOption1  = yyResult.index;
              yyOpValue1 = v$el$3;
            }
            { // Start scope for v$g$4.
              final Node v$g$4 = cast(yyOpValue1);

              yyResult = pAspectCompoundStatement(yyOption1);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {
                final Node v$g$5 = yyResult.semanticValue();

                yyValue = GNode.create("AspectFunctionDefinition", v$g$1, v$g$2, v$g$3, v$g$4, v$g$5);
                yyValue.setLocation(location(yyStart));

                return yyResult.createValue(yyValue, yyError);
              }
            } // End scope for v$g$4.
          }
        }
      } // End scope for v$g$2.
    } // End scope for v$g$1.

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AspectCompoundStatement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAspectCompoundStatement(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbol(yyStart);
    if (yyResult.hasValue("{")) {

      yyResult = pPushScope(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyRepetition1 = yyResult.index;
        yyRepValue1   = Pair.empty();
        while (true) {

          yyResult = pLocalLabelDeclaration(yyRepetition1);
          yyError  = yyResult.select(yyError, yyRepetition1);
          if (yyResult.hasValue()) {
            final Node v$el$1 = yyResult.semanticValue();

            yyRepetition1 = yyResult.index;
            yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
            continue;
          }
          break;
        }
        { // Start scope for v$g$1.
          final Pair<Node> v$g$1 = yyRepValue1.reverse();

          yyResult = pBeginningAdviceStatementList(yyRepetition1);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {
            final Node v$g$2 = yyResult.semanticValue();

            yyResult = pAspectFunctionBody(yyResult.index);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {
              final Node v$g$3 = yyResult.semanticValue();

              yyResult = pEndingAdviceStatementList(yyResult.index);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {
                final Node v$g$4 = yyResult.semanticValue();

                yyResult = pAnnotations(yyResult.index);
                yyError  = yyResult.select(yyError);
                if (yyResult.hasValue()) {
                  final Node v$g$5 = yyResult.semanticValue();

                  yyBase   = yyResult.index;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyResult = pPopScope(yyResult.index);
                    yyError  = yyResult.select(yyError);
                    if (yyResult.hasValue()) {

                      yyValue = GNode.create("AspectCompoundStatement", v$g$1.size() + 4).
                        addAll(v$g$1).add(v$g$2).add(v$g$3).add(v$g$4).add(v$g$5);
                      yyValue.setLocation(location(yyStart));

                      return yyResult.createValue(yyValue, yyError);
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                }
              }
            }
          }
        } // End scope for v$g$1.
      }
    }

    // Done.
    yyError = yyError.select("aspect compound statement expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.BeginningAdviceStatementList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBeginningAdviceStatementList(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pBeginningAdviceStatement(yyRepetition1);
      yyError  = yyResult.select(yyError, yyRepetition1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }
    { // Start scope for v$g$1.
      final Pair<Node> v$g$1 = yyRepValue1.reverse();

      yyValue = GNode.createFromPair("BeginningAdviceStatementList", v$g$1);
      yyValue.setLocation(location(yyStart));

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    } // End scope for v$g$1.
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.EndingAdviceStatementList.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEndingAdviceStatementList(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pEndingAdviceStatement(yyRepetition1);
      yyError  = yyResult.select(yyError, yyRepetition1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }
    { // Start scope for v$g$1.
      final Pair<Node> v$g$1 = yyRepValue1.reverse();

      yyValue = GNode.createFromPair("EndingAdviceStatementList", v$g$1);
      yyValue.setLocation(location(yyStart));

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    } // End scope for v$g$1.
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AspectFunctionBody.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAspectFunctionBody(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepValue1   = Pair.empty();
    while (true) {

      yyResult = pDeclarationOrStatement(yyRepetition1);
      yyError  = yyResult.select(yyError, yyRepetition1);
      if (yyResult.hasValue()) {
        final Node v$el$1 = yyResult.semanticValue();

        yyRepetition1 = yyResult.index;
        yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
        continue;
      }
      break;
    }
    { // Start scope for v$g$1.
      final Pair<Node> v$g$1 = yyRepValue1.reverse();

      yyValue = GNode.createFromPair("AspectFunctionBody", v$g$1);
      yyValue.setLocation(location(yyStart));

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    } // End scope for v$g$1.
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.BeginningAdviceStatement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBeginningAdviceStatement(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <BeforeAdvice>.

    yyResult = pBeforeAdviceStatement(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node bas = yyResult.semanticValue();

      yyValue = bas;

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <AroundAdvice>.

    yyResult = pAroundAdviceStatement(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node aras = yyResult.semanticValue();

      yyValue = aras;

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.EndingAdviceStatement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEndingAdviceStatement(final int yyStart) 
    throws IOException {

    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <AfterAdvice>.

    yyResult = pAfterAdviceStatement(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Node aas = yyResult.semanticValue();

      yyValue = aas;

      setLocation(yyValue, yyStart);
      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.BeforeAdviceStatement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBeforeAdviceStatement(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("advice_before")) {
      final String v$g$1 = "advice_before";

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pIdentifier(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String adviceName = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue("{")) {

              yyResult = pPushScope(yyResult.index);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {

                yyState.setAdvice(adviceName);

                yyRepetition1 = yyResult.index;
                yyRepValue1   = Pair.empty();
                while (true) {

                  yyResult = pDeclarationOrStatement(yyRepetition1);
                  yyError  = yyResult.select(yyError, yyRepetition1);
                  if (yyResult.hasValue()) {
                    final Node v$el$1 = yyResult.semanticValue();

                    yyRepetition1 = yyResult.index;
                    yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
                    continue;
                  }
                  break;
                }
                { // Start scope for v$g$2.
                  final Pair<Node> v$g$2 = yyRepValue1.reverse();

                  yyBase   = yyRepetition1;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyBase   = yyResult.index;
                    yyResult = pSymbol(yyBase);
                    if (yyResult.hasValue(";")) {

                      yyResult = pPopScope(yyResult.index);
                      yyError  = yyResult.select(yyError);
                      if (yyResult.hasValue()) {

                        yyValue = GNode.create("BeforeAdviceStatement", v$g$2.size() + 2).
                          add(v$g$1).add(adviceName).addAll(v$g$2);
                        yyValue.setLocation(location(yyStart));

                        return yyResult.createValue(yyValue, yyError);
                      }
                    } else {
                      yyError = yyError.select("';' expected", yyBase);
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                } // End scope for v$g$2.
              }
            } else {
              yyError = yyError.select("'{' expected", yyBase);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Done.
    yyError = yyError.select("before advice statement expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AfterAdviceStatement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAfterAdviceStatement(final int yyStart) throws IOException {
    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("advice_after")) {
      final String v$g$1 = "advice_after";

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pIdentifier(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String adviceName = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue("{")) {

              yyResult = pPushScope(yyResult.index);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {

                yyState.setAdvice(adviceName);

                yyRepetition1 = yyResult.index;
                yyRepValue1   = Pair.empty();
                while (true) {

                  yyResult = pDeclarationOrStatement(yyRepetition1);
                  yyError  = yyResult.select(yyError, yyRepetition1);
                  if (yyResult.hasValue()) {
                    final Node v$el$1 = yyResult.semanticValue();

                    yyRepetition1 = yyResult.index;
                    yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
                    continue;
                  }
                  break;
                }
                { // Start scope for v$g$2.
                  final Pair<Node> v$g$2 = yyRepValue1.reverse();

                  yyBase   = yyRepetition1;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyBase   = yyResult.index;
                    yyResult = pSymbol(yyBase);
                    if (yyResult.hasValue(";")) {

                      yyResult = pPopScope(yyResult.index);
                      yyError  = yyResult.select(yyError);
                      if (yyResult.hasValue()) {

                        yyValue = GNode.create("AfterAdviceStatement", v$g$2.size() + 2).
                          add(v$g$1).add(adviceName).addAll(v$g$2);
                        yyValue.setLocation(location(yyStart));

                        return yyResult.createValue(yyValue, yyError);
                      }
                    } else {
                      yyError = yyError.select("';' expected", yyBase);
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                } // End scope for v$g$2.
              }
            } else {
              yyError = yyError.select("'{' expected", yyBase);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Done.
    yyError = yyError.select("after advice statement expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.c4.C4.AroundAdviceStatement.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pAroundAdviceStatement(final int yyStart) 
    throws IOException {

    Result     yyResult;
    int        yyBase;
    int        yyRepetition1;
    Pair<Node> yyRepValue1;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pKeyword(yyStart);
    if (yyResult.hasValue("advice_around")) {
      final String v$g$1 = "advice_around";

      yyBase   = yyResult.index;
      yyResult = pSymbol(yyBase);
      if (yyResult.hasValue("(")) {

        yyResult = pIdentifier(yyResult.index);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String adviceName = yyResult.semanticValue();

          yyBase   = yyResult.index;
          yyResult = pSymbol(yyBase);
          if (yyResult.hasValue(")")) {

            yyBase   = yyResult.index;
            yyResult = pSymbol(yyBase);
            if (yyResult.hasValue("{")) {

              yyResult = pPushScope(yyResult.index);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {

                yyState.setAdvice(adviceName);

                yyRepetition1 = yyResult.index;
                yyRepValue1   = Pair.empty();
                while (true) {

                  yyResult = pDeclarationOrStatement(yyRepetition1);
                  yyError  = yyResult.select(yyError, yyRepetition1);
                  if (yyResult.hasValue()) {
                    final Node v$el$1 = yyResult.semanticValue();

                    yyRepetition1 = yyResult.index;
                    yyRepValue1   = new Pair<Node>(v$el$1, yyRepValue1);
                    continue;
                  }
                  break;
                }
                { // Start scope for v$g$2.
                  final Pair<Node> v$g$2 = yyRepValue1.reverse();

                  yyBase   = yyRepetition1;
                  yyResult = pSymbol(yyBase);
                  if (yyResult.hasValue("}")) {

                    yyBase   = yyResult.index;
                    yyResult = pSymbol(yyBase);
                    if (yyResult.hasValue(";")) {

                      yyResult = pPopScope(yyResult.index);
                      yyError  = yyResult.select(yyError);
                      if (yyResult.hasValue()) {

                        yyValue = GNode.create("AroundAdviceStatement", v$g$2.size() + 2).
                          add(v$g$1).add(adviceName).addAll(v$g$2);
                        yyValue.setLocation(location(yyStart));

                        return yyResult.createValue(yyValue, yyError);
                      }
                    } else {
                      yyError = yyError.select("';' expected", yyBase);
                    }
                  } else {
                    yyError = yyError.select("'}' expected", yyBase);
                  }
                } // End scope for v$g$2.
              }
            } else {
              yyError = yyError.select("'{' expected", yyBase);
            }
          } else {
            yyError = yyError.select("')' expected", yyBase);
          }
        }
      } else {
        yyError = yyError.select("'(' expected", yyBase);
      }
    }

    // Done.
    yyError = yyError.select("around advice statement expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.Constant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pConstant(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pFloatingConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 2.

    yyResult = pIntegerConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 3.

    yyResult = pCharacterConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative 4.

    yyResult = pStringConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.IntegerConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pIntegerConstant(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Hex>.

    yyResult = pHexConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$1 = yyResult.semanticValue();

      yyValue = GNode.create("IntegerConstant", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Octal>.

    yyResult = pOctalConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$2 = yyResult.semanticValue();

      yyValue = GNode.create("IntegerConstant", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Decimal>.

    yyResult = pDecimalConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$3 = yyResult.semanticValue();

      yyValue = GNode.create("IntegerConstant", v$g$3);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.DecimalConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDecimalConstant(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyRepetition1;
    int        yyOption1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
      case '8':
      case '9':
        {
          yyRepetition1 = yyIndex;
          while (true) {

            yyC = character(yyRepetition1);
            if (-1 != yyC) {
              yyIndex = yyRepetition1 + 1;

              switch (yyC) {
              case '0':
              case '1':
              case '2':
              case '3':
              case '4':
              case '5':
              case '6':
              case '7':
              case '8':
              case '9':
                {
                  yyRepetition1 = yyIndex;
                  continue;
                }

              default:
                /* No match. */
              }
            }
            break;
          }

          yyOption1  = yyRepetition1;

          yyResult = pIntegerSuffix(yyOption1);
          yyError  = yyResult.select(yyError, yyOption1);
          if (yyResult.hasValue()) {

            yyOption1  = yyResult.index;
          }

          yyValue = difference(yyStart, yyOption1);

          return new SemanticValue(yyValue, yyOption1, yyError);
        }

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("decimal constant expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.HexConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pHexConstant(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    int        yyOption1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pHexPrefix(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      yyRepetition1 = yyResult.index;
      yyRepeated1   = false;
      while (true) {

        yyC = character(yyRepetition1);
        if (-1 != yyC) {
          yyIndex = yyRepetition1 + 1;

          switch (yyC) {
          case '0':
          case '1':
          case '2':
          case '3':
          case '4':
          case '5':
          case '6':
          case '7':
          case '8':
          case '9':
          case 'A':
          case 'B':
          case 'C':
          case 'D':
          case 'E':
          case 'F':
          case 'a':
          case 'b':
          case 'c':
          case 'd':
          case 'e':
          case 'f':
            {
              yyRepetition1 = yyIndex;
              yyRepeated1   = true;
              continue;
            }

          default:
            /* No match. */
          }
        }
        break;
      }

      if (yyRepeated1) {

        yyOption1  = yyRepetition1;

        yyResult = pIntegerSuffix(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {

          yyOption1  = yyResult.index;
        }

        yyValue = difference(yyStart, yyOption1);

        return new SemanticValue(yyValue, yyOption1, yyError);
      }
    }

    // Done.
    yyError = yyError.select("hex constant expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.HexPrefix.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pHexPrefix(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if ('0' == yyC) {
      yyIndex = yyStart + 1;

      yyC = character(yyIndex);
      if (-1 != yyC) {
        yyIndex = yyIndex + 1;

        switch (yyC) {
        case 'X':
        case 'x':
          {
            yyValue = null;

            return new SemanticValue(yyValue, yyIndex, yyError);
          }

        default:
          /* No match. */
        }
      }
    }

    // Done.
    yyError = yyError.select("hex prefix expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.OctalConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pOctalConstant(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyRepetition1;
    int        yyOption1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if ('0' == yyC) {
      yyIndex = yyStart + 1;

      yyRepetition1 = yyIndex;
      while (true) {

        yyC = character(yyRepetition1);
        if (-1 != yyC) {
          yyIndex = yyRepetition1 + 1;

          switch (yyC) {
          case '0':
          case '1':
          case '2':
          case '3':
          case '4':
          case '5':
          case '6':
          case '7':
            {
              yyRepetition1 = yyIndex;
              continue;
            }

          default:
            /* No match. */
          }
        }
        break;
      }

      yyOption1  = yyRepetition1;

      yyResult = pIntegerSuffix(yyOption1);
      yyError  = yyResult.select(yyError, yyOption1);
      if (yyResult.hasValue()) {

        yyOption1  = yyResult.index;
      }

      yyValue = difference(yyStart, yyOption1);

      return new SemanticValue(yyValue, yyOption1, yyError);
    }

    // Done.
    yyError = yyError.select("octal constant expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.IntegerSuffix.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pIntegerSuffix(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pLongLongSuffix(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyC = character(yyChoice1);
      if (-1 != yyC) {
        yyIndex = yyChoice1 + 1;

        switch (yyC) {
        case 'U':
        case 'u':
          {
            yyValue = null;

            return new SemanticValue(yyValue, yyIndex, yyError);
          }

        default:
          /* No match. */
        }
      }

      // Nested alternative 2.

      yyValue = null;

      return new SemanticValue(yyValue, yyChoice1, yyError);
    }

    // Alternative 2.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case 'L':
      case 'l':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case 'U':
            case 'u':
              {
                yyValue = null;

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyValue = null;

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case 'U':
      case 'u':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case 'l':
              {
                yyC = character(yyIndex);
                if (-1 != yyC) {
                  yyIndex = yyIndex + 1;
                  if ('l' == yyC) {

                    yyValue = null;

                    return new SemanticValue(yyValue, yyIndex, yyError);
                  }
                }
              }
              break;

            case 'L':
              {
                yyC = character(yyIndex);
                if (-1 != yyC) {
                  yyIndex = yyIndex + 1;
                  if ('L' == yyC) {

                    yyValue = null;

                    return new SemanticValue(yyValue, yyIndex, yyError);
                  }
                }
              }
              break;

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case 'L':
            case 'l':
              {
                yyValue = null;

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 3.

          yyValue = null;

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("integer suffix expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.LongLongSuffix.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLongLongSuffix(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case 'l':
        {
          yyC = character(yyIndex);
          if (-1 != yyC) {
            yyIndex = yyIndex + 1;
            if ('l' == yyC) {

              yyValue = null;

              return new SemanticValue(yyValue, yyIndex, yyError);
            }
          }
        }
        break;

      case 'L':
        {
          yyC = character(yyIndex);
          if (-1 != yyC) {
            yyIndex = yyIndex + 1;
            if ('L' == yyC) {

              yyValue = null;

              return new SemanticValue(yyValue, yyIndex, yyError);
            }
          }
        }
        break;

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("long long suffix expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.FloatingConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pFloatingConstant(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative <Decimal>.

    yyResult = pDecimalFloatingConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$1 = yyResult.semanticValue();

      yyValue = GNode.create("FloatingConstant", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Alternative <Hex>.

    yyResult = pHexFloatingConstant(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$2 = yyResult.semanticValue();

      yyValue = GNode.create("FloatingConstant", v$g$2);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.DecimalFloatingConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDecimalFloatingConstant(final int yyStart) 
    throws IOException {

    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    int        yyOption1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    while (true) {

      yyC = character(yyRepetition1);
      if (-1 != yyC) {
        yyIndex = yyRepetition1 + 1;

        switch (yyC) {
        case '0':
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
          {
            yyRepetition1 = yyIndex;
            yyRepeated1   = true;
            continue;
          }

        default:
          /* No match. */
        }
      }
      break;
    }

    if (yyRepeated1) {

      yyC = character(yyRepetition1);
      if ('.' == yyC) {
        yyIndex = yyRepetition1 + 1;

        yyRepetition1 = yyIndex;
        while (true) {

          yyC = character(yyRepetition1);
          if (-1 != yyC) {
            yyIndex = yyRepetition1 + 1;

            switch (yyC) {
            case '0':
            case '1':
            case '2':
            case '3':
            case '4':
            case '5':
            case '6':
            case '7':
            case '8':
            case '9':
              {
                yyRepetition1 = yyIndex;
                continue;
              }

            default:
              /* No match. */
            }
          }
          break;
        }

        yyOption1  = yyRepetition1;

        yyResult = pExponent(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {

          yyOption1  = yyResult.index;
        }


        yyC = character(yyOption1);
        if (-1 != yyC) {
          yyIndex = yyOption1 + 1;

          switch (yyC) {
          case 'F':
          case 'L':
          case 'f':
          case 'l':
            {
              yyOption1  = yyIndex;
            }
            break;

          default:
            /* No match. */
          }
        }

        yyValue = difference(yyStart, yyOption1);

        return new SemanticValue(yyValue, yyOption1, yyError);
      }
    }

    // Alternative 2.

    yyC = character(yyStart);
    if ('.' == yyC) {
      yyIndex = yyStart + 1;

      yyRepetition1 = yyIndex;
      yyRepeated1   = false;
      while (true) {

        yyC = character(yyRepetition1);
        if (-1 != yyC) {
          yyIndex = yyRepetition1 + 1;

          switch (yyC) {
          case '0':
          case '1':
          case '2':
          case '3':
          case '4':
          case '5':
          case '6':
          case '7':
          case '8':
          case '9':
            {
              yyRepetition1 = yyIndex;
              yyRepeated1   = true;
              continue;
            }

          default:
            /* No match. */
          }
        }
        break;
      }

      if (yyRepeated1) {

        yyOption1  = yyRepetition1;

        yyResult = pExponent(yyOption1);
        yyError  = yyResult.select(yyError, yyOption1);
        if (yyResult.hasValue()) {

          yyOption1  = yyResult.index;
        }


        yyC = character(yyOption1);
        if (-1 != yyC) {
          yyIndex = yyOption1 + 1;

          switch (yyC) {
          case 'F':
          case 'L':
          case 'f':
          case 'l':
            {
              yyOption1  = yyIndex;
            }
            break;

          default:
            /* No match. */
          }
        }

        yyValue = difference(yyStart, yyOption1);

        return new SemanticValue(yyValue, yyOption1, yyError);
      }
    }

    // Alternative 3.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    while (true) {

      yyC = character(yyRepetition1);
      if (-1 != yyC) {
        yyIndex = yyRepetition1 + 1;

        switch (yyC) {
        case '0':
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
          {
            yyRepetition1 = yyIndex;
            yyRepeated1   = true;
            continue;
          }

        default:
          /* No match. */
        }
      }
      break;
    }

    if (yyRepeated1) {

      yyResult = pExponent(yyRepetition1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyOption1  = yyResult.index;

        yyC = character(yyOption1);
        if (-1 != yyC) {
          yyIndex = yyOption1 + 1;

          switch (yyC) {
          case 'F':
          case 'L':
          case 'f':
          case 'l':
            {
              yyOption1  = yyIndex;
            }
            break;

          default:
            /* No match. */
          }
        }

        yyValue = difference(yyStart, yyOption1);

        return new SemanticValue(yyValue, yyOption1, yyError);
      }
    }

    // Done.
    yyError = yyError.select("decimal floating constant expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.HexFloatingConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pHexFloatingConstant(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    int        yyOption1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pHexPrefix(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyRepetition1 = yyChoice1;
      yyRepeated1   = false;
      while (true) {

        yyC = character(yyRepetition1);
        if (-1 != yyC) {
          yyIndex = yyRepetition1 + 1;

          switch (yyC) {
          case '0':
          case '1':
          case '2':
          case '3':
          case '4':
          case '5':
          case '6':
          case '7':
          case '8':
          case '9':
          case 'A':
          case 'B':
          case 'C':
          case 'D':
          case 'E':
          case 'F':
          case 'a':
          case 'b':
          case 'c':
          case 'd':
          case 'e':
          case 'f':
            {
              yyRepetition1 = yyIndex;
              yyRepeated1   = true;
              continue;
            }

          default:
            /* No match. */
          }
        }
        break;
      }

      if (yyRepeated1) {

        yyC = character(yyRepetition1);
        if ('.' == yyC) {
          yyIndex = yyRepetition1 + 1;

          yyRepetition1 = yyIndex;
          while (true) {

            yyC = character(yyRepetition1);
            if (-1 != yyC) {
              yyIndex = yyRepetition1 + 1;

              switch (yyC) {
              case '0':
              case '1':
              case '2':
              case '3':
              case '4':
              case '5':
              case '6':
              case '7':
              case '8':
              case '9':
              case 'A':
              case 'B':
              case 'C':
              case 'D':
              case 'E':
              case 'F':
              case 'a':
              case 'b':
              case 'c':
              case 'd':
              case 'e':
              case 'f':
                {
                  yyRepetition1 = yyIndex;
                  continue;
                }

              default:
                /* No match. */
              }
            }
            break;
          }

          yyResult = pBinaryExponent(yyRepetition1);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {

            yyOption1  = yyResult.index;

            yyC = character(yyOption1);
            if (-1 != yyC) {
              yyIndex = yyOption1 + 1;

              switch (yyC) {
              case 'F':
              case 'L':
              case 'f':
              case 'l':
                {
                  yyOption1  = yyIndex;
                }
                break;

              default:
                /* No match. */
              }
            }

            yyValue = difference(yyStart, yyOption1);

            return new SemanticValue(yyValue, yyOption1, yyError);
          }
        }
      }

      // Nested alternative 2.

      yyC = character(yyChoice1);
      if ('.' == yyC) {
        yyIndex = yyChoice1 + 1;

        yyRepetition1 = yyIndex;
        yyRepeated1   = false;
        while (true) {

          yyC = character(yyRepetition1);
          if (-1 != yyC) {
            yyIndex = yyRepetition1 + 1;

            switch (yyC) {
            case '0':
            case '1':
            case '2':
            case '3':
            case '4':
            case '5':
            case '6':
            case '7':
            case '8':
            case '9':
            case 'A':
            case 'B':
            case 'C':
            case 'D':
            case 'E':
            case 'F':
            case 'a':
            case 'b':
            case 'c':
            case 'd':
            case 'e':
            case 'f':
              {
                yyRepetition1 = yyIndex;
                yyRepeated1   = true;
                continue;
              }

            default:
              /* No match. */
            }
          }
          break;
        }

        if (yyRepeated1) {

          yyResult = pBinaryExponent(yyRepetition1);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {

            yyOption1  = yyResult.index;

            yyC = character(yyOption1);
            if (-1 != yyC) {
              yyIndex = yyOption1 + 1;

              switch (yyC) {
              case 'F':
              case 'L':
              case 'f':
              case 'l':
                {
                  yyOption1  = yyIndex;
                }
                break;

              default:
                /* No match. */
              }
            }

            yyValue = difference(yyStart, yyOption1);

            return new SemanticValue(yyValue, yyOption1, yyError);
          }
        }
      }

      // Nested alternative 3.

      yyRepetition1 = yyChoice1;
      yyRepeated1   = false;
      while (true) {

        yyC = character(yyRepetition1);
        if (-1 != yyC) {
          yyIndex = yyRepetition1 + 1;

          switch (yyC) {
          case '0':
          case '1':
          case '2':
          case '3':
          case '4':
          case '5':
          case '6':
          case '7':
          case '8':
          case '9':
          case 'A':
          case 'B':
          case 'C':
          case 'D':
          case 'E':
          case 'F':
          case 'a':
          case 'b':
          case 'c':
          case 'd':
          case 'e':
          case 'f':
            {
              yyRepetition1 = yyIndex;
              yyRepeated1   = true;
              continue;
            }

          default:
            /* No match. */
          }
        }
        break;
      }

      if (yyRepeated1) {

        yyResult = pBinaryExponent(yyRepetition1);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {

          yyOption1  = yyResult.index;

          yyC = character(yyOption1);
          if (-1 != yyC) {
            yyIndex = yyOption1 + 1;

            switch (yyC) {
            case 'F':
            case 'L':
            case 'f':
            case 'l':
              {
                yyOption1  = yyIndex;
              }
              break;

            default:
              /* No match. */
            }
          }

          yyValue = difference(yyStart, yyOption1);

          return new SemanticValue(yyValue, yyOption1, yyError);
        }
      }
    }

    // Done.
    yyError = yyError.select("hex floating constant expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.Exponent.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pExponent(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fExponent) 
      yyColumn.chunk4.fExponent = pExponent$1(yyStart);
    return yyColumn.chunk4.fExponent;
  }

  /** Actually parse xtc.lang.CConstant.Exponent. */
  private Result pExponent$1(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyOption1;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case 'E':
      case 'e':
        {
          yyOption1  = yyIndex;

          yyC = character(yyOption1);
          if (-1 != yyC) {
            yyIndex = yyOption1 + 1;

            switch (yyC) {
            case '+':
            case '-':
              {
                yyOption1  = yyIndex;
              }
              break;

            default:
              /* No match. */
            }
          }

          yyResult = p$$Shared2(yyOption1);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {

            yyValue = null;

            return yyResult.createValue(yyValue, yyError);
          }
        }
        break;

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("exponent expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.$$Shared2.
   * This nonterminal represents the duplicate productions 
   * xtc.lang.c4.C4.Exponent$$Plus1 and xtc.lang.c4.C4.BinaryExponent$$Plus1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result p$$Shared2(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.f$$Shared2) 
      yyColumn.chunk4.f$$Shared2 = p$$Shared2$1(yyStart);
    return yyColumn.chunk4.f$$Shared2;
  }

  /** Actually parse xtc.lang.c4.C4.$$Shared2. */
  private Result p$$Shared2$1(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case '0':
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
      case '8':
      case '9':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyResult = p$$Shared2(yyChoice1);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {

            yyValue = null;

            return yyResult.createValue(yyValue, yyError);
          }

          // Nested alternative 2.

          yyValue = null;

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select(" expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.BinaryExponent.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pBinaryExponent(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fBinaryExponent) 
      yyColumn.chunk4.fBinaryExponent = pBinaryExponent$1(yyStart);
    return yyColumn.chunk4.fBinaryExponent;
  }

  /** Actually parse xtc.lang.CConstant.BinaryExponent. */
  private Result pBinaryExponent$1(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyOption1;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case 'P':
      case 'p':
        {
          yyOption1  = yyIndex;

          yyC = character(yyOption1);
          if (-1 != yyC) {
            yyIndex = yyOption1 + 1;

            switch (yyC) {
            case '+':
            case '-':
              {
                yyOption1  = yyIndex;
              }
              break;

            default:
              /* No match. */
            }
          }

          yyResult = p$$Shared2(yyOption1);
          yyError  = yyResult.select(yyError);
          if (yyResult.hasValue()) {

            yyValue = null;

            return yyResult.createValue(yyValue, yyError);
          }
        }
        break;

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("binary exponent expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.CharacterConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pCharacterConstant(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pWideCharacterLiteral(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$1 = yyResult.semanticValue();

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyValue = GNode.create("CharacterConstant", v$g$1);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 2.

    yyResult = pCharacterLiteral(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$g$2 = yyResult.semanticValue();

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyValue = GNode.create("CharacterConstant", v$g$2);
        yyValue.setLocation(location(yyStart));

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.WideCharacterLiteral.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pWideCharacterLiteral(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if ('L' == yyC) {
      yyIndex = yyStart + 1;

      yyResult = pCharacterLiteral(yyIndex);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyValue = difference(yyStart, yyResult.index);

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("wide character literal expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.CharacterLiteral.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pCharacterLiteral(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fCharacterLiteral) 
      yyColumn.chunk4.fCharacterLiteral = pCharacterLiteral$1(yyStart);
    return yyColumn.chunk4.fCharacterLiteral;
  }

  /** Actually parse xtc.lang.CConstant.CharacterLiteral. */
  private Result pCharacterLiteral$1(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if ('\'' == yyC) {
      yyIndex = yyStart + 1;

      yyResult = pCharacterContents(yyIndex);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyC = character(yyResult.index);
        if ('\'' == yyC) {
          yyIndex = yyResult.index + 1;

          yyValue = difference(yyStart, yyIndex);

          return new SemanticValue(yyValue, yyIndex, yyError);
        }
      }
    }

    // Done.
    yyError = yyError.select("character literal expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.CharacterContents.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pCharacterContents(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyRepetition1;
    boolean    yyRepeated1;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    yyRepeated1   = false;
    while (true) {

      final int yyChoice1 = yyRepetition1;

      // Nested alternative 1.

      yyC = character(yyChoice1);
      if (-1 != yyC) {
        yyIndex = yyChoice1 + 1;

        switch (yyC) {
        case '\\':
          {
            final int yyChoice2 = yyIndex;

            // Nested alternative 1.

            yyResult = pEscapeCode(yyChoice2);
            yyError  = yyResult.select(yyError);
            if (yyResult.hasValue()) {

              yyRepetition1 = yyResult.index;
              yyRepeated1   = true;
              continue;
            }

            // Nested alternative 2.

            yyC = character(yyChoice2);
            if (-1 != yyC) {
              yyIndex = yyChoice2 + 1;

              switch (yyC) {
              case 'u':
                {
                  yyResult = pHexQuad(yyIndex);
                  yyError  = yyResult.select(yyError);
                  if (yyResult.hasValue()) {

                    yyRepetition1 = yyResult.index;
                    yyRepeated1   = true;
                    continue;
                  }
                }
                break;

              case 'U':
                {
                  yyResult = pHexQuad(yyIndex);
                  yyError  = yyResult.select(yyError);
                  if (yyResult.hasValue()) {

                    yyResult = pHexQuad(yyResult.index);
                    yyError  = yyResult.select(yyError);
                    if (yyResult.hasValue()) {

                      yyRepetition1 = yyResult.index;
                      yyRepeated1   = true;
                      continue;
                    }
                  }
                }
                break;

              default:
                /* No match. */
              }
            }
          }
          break;

        default:
          /* No match. */
        }
      }

      // Nested alternative 2.

      yyC = character(yyChoice1);
      if (-1 != yyC) {
        yyIndex = yyChoice1 + 1;

        switch (yyC) {
        case '\n':
        case '\r':
        case '\'':
        case '\\':
          /* No match. */
          break;

        default:
          {
            yyRepetition1 = yyIndex;
            yyRepeated1   = true;
            continue;
          }
        }
      }
      break;
    }

    if (yyRepeated1) {

      yyValue = null;

      return new SemanticValue(yyValue, yyRepetition1, yyError);
    }

    // Done.
    yyError = yyError.select("character contents expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.StringConstant.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStringConstant(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fStringConstant) 
      yyColumn.chunk4.fStringConstant = pStringConstant$1(yyStart);
    return yyColumn.chunk4.fStringConstant;
  }

  /** Actually parse xtc.lang.CConstant.StringConstant. */
  private Result pStringConstant$1(final int yyStart) throws IOException {
    Result     yyResult;
    Node       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pStringConstant$$Plus1(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final Pair<String> v$g$1 = yyResult.semanticValue();

      yyValue = GNode.createFromPair("StringConstant", v$g$1);
      yyValue.setLocation(location(yyStart));

      return yyResult.createValue(yyValue, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.StringConstant$$Choice1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStringConstant$$Choice1(final int yyStart) 
    throws IOException {

    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pWideStringLiteral(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Alternative 2.

    yyResult = pStringLiteral(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse synthetic nonterminal xtc.lang.c4.C4.StringConstant$$Plus1.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStringConstant$$Plus1(final int yyStart) 
    throws IOException {

    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fStringConstant$$Plus1) 
      yyColumn.chunk4.fStringConstant$$Plus1 = pStringConstant$$Plus1$1(yyStart);
    return yyColumn.chunk4.fStringConstant$$Plus1;
  }

  /** Actually parse xtc.lang.c4.C4.StringConstant$$Plus1. */
  private Result pStringConstant$$Plus1$1(final int yyStart) 
    throws IOException {

    Result       yyResult;
    Pair<String> yyValue;
    ParseError   yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pStringConstant$$Choice1(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      final String v$el$1 = yyResult.semanticValue();

      final int yyChoice1 = yyResult.index;

      // Nested alternative 1.

      yyResult = pStringConstant$$Plus1(yyChoice1);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {
        final Pair<String> v$4 = yyResult.semanticValue();

        yyValue = new Pair<String>(v$el$1, v$4);

        return yyResult.createValue(yyValue, yyError);
      }

      // Nested alternative 2.

      yyValue = new Pair<String>(v$el$1);

      return new SemanticValue(yyValue, yyChoice1, yyError);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.WideStringLiteral.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pWideStringLiteral(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if ('L' == yyC) {
      yyIndex = yyStart + 1;

      yyResult = pStringLiteral(yyIndex);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyValue = difference(yyStart, yyResult.index);

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("wide string literal expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.StringLiteral.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStringLiteral(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk4) yyColumn.chunk4 = new Chunk4();
    if (null == yyColumn.chunk4.fStringLiteral) 
      yyColumn.chunk4.fStringLiteral = pStringLiteral$1(yyStart);
    return yyColumn.chunk4.fStringLiteral;
  }

  /** Actually parse xtc.lang.CConstant.StringLiteral. */
  private Result pStringLiteral$1(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if ('\"' == yyC) {
      yyIndex = yyStart + 1;

      yyResult = pStringContents(yyIndex);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        yyC = character(yyResult.index);
        if ('\"' == yyC) {
          yyIndex = yyResult.index + 1;

          yyValue = difference(yyStart, yyIndex);

          return new SemanticValue(yyValue, yyIndex, yyError);
        }
      }
    }

    // Done.
    yyError = yyError.select("string literal expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.StringContents.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pStringContents(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    int        yyRepetition1;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    while (true) {

      final int yyChoice1 = yyRepetition1;

      // Nested alternative 1.

      yyC = character(yyChoice1);
      if (-1 != yyC) {
        yyIndex = yyChoice1 + 1;

        switch (yyC) {
        case '\\':
          {
            final int yyChoice2 = yyIndex;

            // Nested alternative 1.

            yyResult = pEscapeCode(yyChoice2);
            yyError  = yyResult.select(yyError, yyRepetition1);
            if (yyResult.hasValue()) {

              yyRepetition1 = yyResult.index;
              continue;
            }

            // Nested alternative 2.

            yyC = character(yyChoice2);
            if (-1 != yyC) {
              yyIndex = yyChoice2 + 1;

              switch (yyC) {
              case 'u':
                {
                  yyResult = pHexQuad(yyIndex);
                  yyError  = yyResult.select(yyError, yyRepetition1);
                  if (yyResult.hasValue()) {

                    yyRepetition1 = yyResult.index;
                    continue;
                  }
                }
                break;

              case 'U':
                {
                  yyResult = pHexQuad(yyIndex);
                  yyError  = yyResult.select(yyError, yyRepetition1);
                  if (yyResult.hasValue()) {

                    yyResult = pHexQuad(yyResult.index);
                    yyError  = yyResult.select(yyError, yyRepetition1);
                    if (yyResult.hasValue()) {

                      yyRepetition1 = yyResult.index;
                      continue;
                    }
                  }
                }
                break;

              default:
                /* No match. */
              }
            }
          }
          break;

        default:
          /* No match. */
        }
      }

      // Nested alternative 2.

      yyC = character(yyChoice1);
      if (-1 != yyC) {
        yyIndex = yyChoice1 + 1;

        switch (yyC) {
        case '\n':
        case '\r':
        case '\"':
        case '\\':
          /* No match. */
          break;

        default:
          {
            yyRepetition1 = yyIndex;
            continue;
          }
        }
      }
      break;
    }

    yyValue = null;

    return new SemanticValue(yyValue, yyRepetition1, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.EscapeCode.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEscapeCode(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    int        yyRepetition1;
    boolean    yyRepeated1;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case '\"':
      case '\'':
      case '?':
      case '\\':
      case 'a':
      case 'b':
      case 'f':
      case 'n':
      case 'r':
      case 't':
      case 'v':
        {
          yyValue = null;

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '0':
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case '0':
            case '1':
            case '2':
            case '3':
            case '4':
            case '5':
            case '6':
            case '7':
              {
                final int yyChoice2 = yyIndex;

                // Nested alternative 1.

                yyC = character(yyChoice2);
                if (-1 != yyC) {
                  yyIndex = yyChoice2 + 1;

                  switch (yyC) {
                  case '0':
                  case '1':
                  case '2':
                  case '3':
                  case '4':
                  case '5':
                  case '6':
                  case '7':
                    {
                      yyValue = null;

                      return new SemanticValue(yyValue, yyIndex, yyError);
                    }

                  default:
                    /* No match. */
                  }
                }

                // Nested alternative 2.

                yyValue = null;

                return new SemanticValue(yyValue, yyChoice2, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyValue = null;

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case 'x':
        {
          yyRepetition1 = yyIndex;
          yyRepeated1   = false;
          while (true) {

            yyC = character(yyRepetition1);
            if (-1 != yyC) {
              yyIndex = yyRepetition1 + 1;

              switch (yyC) {
              case '0':
              case '1':
              case '2':
              case '3':
              case '4':
              case '5':
              case '6':
              case '7':
              case '8':
              case '9':
              case 'A':
              case 'B':
              case 'C':
              case 'D':
              case 'E':
              case 'F':
              case 'a':
              case 'b':
              case 'c':
              case 'd':
              case 'e':
              case 'f':
                {
                  yyRepetition1 = yyIndex;
                  yyRepeated1   = true;
                  continue;
                }

              default:
                /* No match. */
              }
            }
            break;
          }

          if (yyRepeated1) {

            yyValue = null;

            return new SemanticValue(yyValue, yyRepetition1, yyError);
          }
        }
        break;

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("escape code expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CConstant.HexQuad.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pHexQuad(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case '0':
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
      case '8':
      case '9':
      case 'A':
      case 'B':
      case 'C':
      case 'D':
      case 'E':
      case 'F':
      case 'a':
      case 'b':
      case 'c':
      case 'd':
      case 'e':
      case 'f':
        {
          yyC = character(yyIndex);
          if (-1 != yyC) {
            yyIndex = yyIndex + 1;

            switch (yyC) {
            case '0':
            case '1':
            case '2':
            case '3':
            case '4':
            case '5':
            case '6':
            case '7':
            case '8':
            case '9':
            case 'A':
            case 'B':
            case 'C':
            case 'D':
            case 'E':
            case 'F':
            case 'a':
            case 'b':
            case 'c':
            case 'd':
            case 'e':
            case 'f':
              {
                yyC = character(yyIndex);
                if (-1 != yyC) {
                  yyIndex = yyIndex + 1;

                  switch (yyC) {
                  case '0':
                  case '1':
                  case '2':
                  case '3':
                  case '4':
                  case '5':
                  case '6':
                  case '7':
                  case '8':
                  case '9':
                  case 'A':
                  case 'B':
                  case 'C':
                  case 'D':
                  case 'E':
                  case 'F':
                  case 'a':
                  case 'b':
                  case 'c':
                  case 'd':
                  case 'e':
                  case 'f':
                    {
                      yyC = character(yyIndex);
                      if (-1 != yyC) {
                        yyIndex = yyIndex + 1;

                        switch (yyC) {
                        case '0':
                        case '1':
                        case '2':
                        case '3':
                        case '4':
                        case '5':
                        case '6':
                        case '7':
                        case '8':
                        case '9':
                        case 'A':
                        case 'B':
                        case 'C':
                        case 'D':
                        case 'E':
                        case 'F':
                        case 'a':
                        case 'b':
                        case 'c':
                        case 'd':
                        case 'e':
                        case 'f':
                          {
                            yyValue = null;

                            return new SemanticValue(yyValue, yyIndex, yyError);
                          }

                        default:
                          /* No match. */
                        }
                      }
                    }
                    break;

                  default:
                    /* No match. */
                  }
                }
              }
              break;

            default:
              /* No match. */
            }
          }
        }
        break;

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("hex quad expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CIdentifier.Identifier.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pIdentifier(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk5) yyColumn.chunk5 = new Chunk5();
    if (null == yyColumn.chunk5.fIdentifier) 
      yyColumn.chunk5.fIdentifier = pIdentifier$1(yyStart);
    return yyColumn.chunk5.fIdentifier;
  }

  /** Actually parse xtc.lang.CIdentifier.Identifier. */
  private Result pIdentifier$1(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pWord(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      if (! contains(C_KEYWORDS, toText(yyValue))) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("identifier expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CIdentifier.Keyword.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pKeyword(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk5) yyColumn.chunk5 = new Chunk5();
    if (null == yyColumn.chunk5.fKeyword) 
      yyColumn.chunk5.fKeyword = pKeyword$1(yyStart);
    return yyColumn.chunk5.fKeyword;
  }

  /** Actually parse xtc.lang.CIdentifier.Keyword. */
  private Result pKeyword$1(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pWord(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      if (contains(C_KEYWORDS, toText(yyValue))) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    yyError = yyError.select("keyword expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CIdentifier.Word.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pWord(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk5) yyColumn.chunk5 = new Chunk5();
    if (null == yyColumn.chunk5.fWord) 
      yyColumn.chunk5.fWord = pWord$1(yyStart);
    return yyColumn.chunk5.fWord;
  }

  /** Actually parse xtc.lang.CIdentifier.Word. */
  private Result pWord$1(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pWordCharacters(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CIdentifier.WordCharacters.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pWordCharacters(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    int        yyRepetition1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;
      if ((('A' <= yyC) && (yyC <= 'Z')) ||
          ('_' == yyC) ||
          (('a' <= yyC) && (yyC <= 'z'))) {

        yyRepetition1 = yyIndex;
        while (true) {

          yyC = character(yyRepetition1);
          if (-1 != yyC) {
            yyIndex = yyRepetition1 + 1;
            if ((('0' <= yyC) && (yyC <= '9')) ||
                (('A' <= yyC) && (yyC <= 'Z')) ||
                ('_' == yyC) ||
                (('a' <= yyC) && (yyC <= 'z'))) {

              yyRepetition1 = yyIndex;
              continue;
            }
          }
          break;
        }

        yyValue = difference(yyStart, yyRepetition1);

        return new SemanticValue(yyValue, yyRepetition1, yyError);
      }
    }

    // Done.
    yyError = yyError.select("word characters expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSymbol.Symbol.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSymbol(final int yyStart) throws IOException {
    C4ParserColumn yyColumn = (C4ParserColumn)column(yyStart);
    if (null == yyColumn.chunk5) yyColumn.chunk5 = new Chunk5();
    if (null == yyColumn.chunk5.fSymbol) 
      yyColumn.chunk5.fSymbol = pSymbol$1(yyStart);
    return yyColumn.chunk5.fSymbol;
  }

  /** Actually parse xtc.lang.CSymbol.Symbol. */
  private Result pSymbol$1(final int yyStart) throws IOException {
    Result     yyResult;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyResult = pSymbolCharacters(yyStart);
    yyError  = yyResult.select(yyError);
    if (yyResult.hasValue()) {
      yyValue = yyResult.semanticValue();

      yyResult = pSpacing(yyResult.index);
      yyError  = yyResult.select(yyError);
      if (yyResult.hasValue()) {

        return yyResult.createValue(yyValue, yyError);
      }
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSymbol.SymbolCharacters.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSymbolCharacters(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case '>':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case '>':
              {
                final int yyChoice2 = yyIndex;

                // Nested alternative 1.

                yyC = character(yyChoice2);
                if (-1 != yyC) {
                  yyIndex = yyChoice2 + 1;
                  if ('=' == yyC) {

                    yyValue = ">>=";

                    return new SemanticValue(yyValue, yyIndex, yyError);
                  }
                }

                // Nested alternative 2.

                yyValue = ">>";

                return new SemanticValue(yyValue, yyChoice2, yyError);
              }

            case '=':
              {
                yyValue = ">=";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyValue = ">";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '<':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case '<':
              {
                final int yyChoice2 = yyIndex;

                // Nested alternative 1.

                yyC = character(yyChoice2);
                if (-1 != yyC) {
                  yyIndex = yyChoice2 + 1;
                  if ('=' == yyC) {

                    yyValue = "<<=";

                    return new SemanticValue(yyValue, yyIndex, yyError);
                  }
                }

                // Nested alternative 2.

                yyValue = "<<";

                return new SemanticValue(yyValue, yyChoice2, yyError);
              }

            case '=':
              {
                yyValue = "<=";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyValue = "<";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '.':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;
            if ('.' == yyC) {

              yyC = character(yyIndex);
              if (-1 != yyC) {
                yyIndex = yyIndex + 1;
                if ('.' == yyC) {

                  yyValue = "...";

                  return new SemanticValue(yyValue, yyIndex, yyError);
                }
              }
            }
          }

          // Nested alternative 2.

          yyValue = ".";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '+':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case '=':
              {
                yyValue = "+=";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            case '+':
              {
                yyValue = "++";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyValue = "+";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '-':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case '=':
              {
                yyValue = "-=";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            case '-':
              {
                yyValue = "--";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            case '>':
              {
                yyValue = "->";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyValue = "-";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '*':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;
            if ('=' == yyC) {

              yyValue = "*=";

              return new SemanticValue(yyValue, yyIndex, yyError);
            }
          }

          // Nested alternative 2.

          yyValue = "*";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '/':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;
            if ('=' == yyC) {

              yyValue = "/=";

              return new SemanticValue(yyValue, yyIndex, yyError);
            }
          }

          // Nested alternative 2.

          yyValue = "/";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '%':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;
            if ('=' == yyC) {

              yyValue = "%=";

              return new SemanticValue(yyValue, yyIndex, yyError);
            }
          }

          // Nested alternative 2.

          yyValue = "%";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '&':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case '=':
              {
                yyValue = "&=";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            case '&':
              {
                yyValue = "&&";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyValue = "&";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '^':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;
            if ('=' == yyC) {

              yyValue = "^=";

              return new SemanticValue(yyValue, yyIndex, yyError);
            }
          }

          // Nested alternative 2.

          yyValue = "^";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '|':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;

            switch (yyC) {
            case '=':
              {
                yyValue = "|=";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            case '|':
              {
                yyValue = "||";

                return new SemanticValue(yyValue, yyIndex, yyError);
              }

            default:
              /* No match. */
            }
          }

          // Nested alternative 2.

          yyValue = "|";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '=':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;
            if ('=' == yyC) {

              yyValue = "==";

              return new SemanticValue(yyValue, yyIndex, yyError);
            }
          }

          // Nested alternative 2.

          yyValue = "=";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '!':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if (-1 != yyC) {
            yyIndex = yyChoice1 + 1;
            if ('=' == yyC) {

              yyValue = "!=";

              return new SemanticValue(yyValue, yyIndex, yyError);
            }
          }

          // Nested alternative 2.

          yyValue = "!";

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case ';':
        {
          yyValue = ";";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case ':':
        {
          yyValue = ":";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case ',':
        {
          yyValue = ",";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '{':
        {
          yyValue = "{";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '}':
        {
          yyValue = "}";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '(':
        {
          yyValue = "(";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case ')':
        {
          yyValue = ")";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '[':
        {
          yyValue = "[";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case ']':
        {
          yyValue = "]";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '~':
        {
          yyValue = "~";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '?':
        {
          yyValue = "?";

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("symbol characters expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSpacing.Spacing.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSpacing(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    Result     yyPredResult;
    boolean    yyPredMatched;
    int        yyBase;
    int        yyRepetition1;
    int        yyRepetition2;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    while (true) {

      final int yyChoice1 = yyRepetition1;

      // Nested alternative 1.

      yyC = character(yyChoice1);
      if (-1 != yyC) {
        yyIndex = yyChoice1 + 1;

        switch (yyC) {
        case ' ':
          {
            yyRepetition1 = yyIndex;
            continue;
          }

        case '\t':
          {
            yyRepetition1 = yyIndex;
            continue;
          }

        case '\f':
          {
            yyRepetition1 = yyIndex;
            continue;
          }

        case '/':
          {
            yyC = character(yyIndex);
            if (-1 != yyC) {
              yyIndex = yyIndex + 1;

              switch (yyC) {
              case '*':
                {
                  yyRepetition2 = yyIndex;
                  while (true) {

                    final int yyChoice2 = yyRepetition2;

                    // Nested alternative 1.

                    yyC = character(yyChoice2);
                    if (-1 != yyC) {
                      yyIndex = yyChoice2 + 1;

                      switch (yyC) {
                      case '*':
                        {
                          yyPredMatched = false;

                          yyC = character(yyIndex);
                          if ('/' == yyC) {

                            yyPredMatched = true;
                          }

                          if (! yyPredMatched) {

                            yyRepetition2 = yyIndex;
                            continue;
                          } else {
                            yyError = yyError.select("spacing expected", yyStart);
                          }
                        }
                        break;

                      default:
                        {
                          yyRepetition2 = yyIndex;
                          continue;
                        }
                      }
                    }
                    break;
                  }

                  yyBase = yyRepetition2;
                  yyC    = character(yyBase);
                  if ('*' == yyC) {
                    yyIndex = yyRepetition2 + 1;

                    yyC = character(yyIndex);
                    if ('/' == yyC) {
                      yyIndex = yyIndex + 1;

                      yyRepetition1 = yyIndex;
                      continue;
                    } else {
                      yyError = yyError.select("'*/' expected", yyBase);
                    }
                  } else {
                    yyError = yyError.select("'*/' expected", yyBase);
                  }
                }
                break;

              case '/':
                {
                  yyRepetition2 = yyIndex;
                  while (true) {

                    yyC = character(yyRepetition2);
                    if (-1 != yyC) {
                      yyIndex = yyRepetition2 + 1;

                      switch (yyC) {
                      case '\n':
                      case '\r':
                        /* No match. */
                        break;

                      default:
                        {
                          yyRepetition2 = yyIndex;
                          continue;
                        }
                      }
                    }
                    break;
                  }

                  yyPredResult = pLineTerminator(yyRepetition2);
                  yyError      = yyPredResult.select(yyError);
                  if (yyPredResult.hasValue()) {

                    yyRepetition1 = yyRepetition2;
                    continue;
                  }
                }
                break;

              default:
                /* No match. */
              }
            }
          }
          break;

        case '\r':
          {
            final int yyChoice2 = yyIndex;

            // Nested alternative 1.

            yyC = character(yyChoice2);
            if ('\n' == yyC) {
              yyIndex = yyChoice2 + 1;

              yyResult = pDirective(yyIndex);
              yyError  = yyResult.select(yyError, yyRepetition1);
              if (yyResult.hasValue()) {

                yyRepetition1 = yyResult.index;
                continue;
              }
            }

            // Nested alternative 2.

            yyResult = pDirective(yyChoice2);
            yyError  = yyResult.select(yyError, yyRepetition1);
            if (yyResult.hasValue()) {

              yyRepetition1 = yyResult.index;
              continue;
            }
          }
          break;

        case '\n':
          {
            yyResult = pDirective(yyIndex);
            yyError  = yyResult.select(yyError, yyRepetition1);
            if (yyResult.hasValue()) {

              yyRepetition1 = yyResult.index;
              continue;
            }
          }
          break;

        default:
          /* No match. */
        }
      }
      break;
    }

    yyValue = null;

    return new SemanticValue(yyValue, yyRepetition1, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSpacing.Space.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pSpace(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case ' ':
        {
          yyValue = null;

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '\t':
        {
          yyValue = null;

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      case '\f':
        {
          yyValue = null;

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("space expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSpacing.LineTerminator.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLineTerminator(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case '\r':
        {
          final int yyChoice1 = yyIndex;

          // Nested alternative 1.

          yyC = character(yyChoice1);
          if ('\n' == yyC) {
            yyIndex = yyChoice1 + 1;

            yyValue = null;

            return new SemanticValue(yyValue, yyIndex, yyError);
          }

          // Nested alternative 2.

          yyValue = null;

          return new SemanticValue(yyValue, yyChoice1, yyError);
        }

      case '\n':
        {
          yyValue = null;

          return new SemanticValue(yyValue, yyIndex, yyError);
        }

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("line terminator expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSpacing.EndOfFile.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEndOfFile(final int yyStart) throws IOException {
    int        yyC;
    boolean    yyPredMatched;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyPredMatched = false;

    yyC = character(yyStart);
    if (-1 != yyC) {

      yyPredMatched = true;
    }

    if (! yyPredMatched) {

      yyValue = null;

      return new SemanticValue(yyValue, yyStart, yyError);
    } else {
      yyError = yyError.select("end of file expected", yyStart);
    }

    // Done.
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSpacing.Directive.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pDirective(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    Result     yyResult;
    Result     yyPredResult;
    int        yyBase;
    int        yyRepetition1;
    boolean    yyRepeated1;
    int        yyOption1;
    String     yyOpValue1;
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if ('#' == yyC) {
      yyIndex = yyStart + 1;

      final int yyChoice1 = yyIndex;

      // Nested alternative 1.

      yyC = character(yyChoice1);
      if (' ' == yyC) {
        yyIndex = yyChoice1 + 1;

        yyResult = pLineNumber(yyIndex);
        yyError  = yyResult.select(yyError);
        if (yyResult.hasValue()) {
          final String line = yyResult.semanticValue();

          yyC = character(yyResult.index);
          if (' ' == yyC) {
            yyIndex = yyResult.index + 1;

            yyC = character(yyIndex);
            if ('\"' == yyC) {
              yyIndex = yyIndex + 1;

              yyResult = pFileName(yyIndex);
              yyError  = yyResult.select(yyError);
              if (yyResult.hasValue()) {
                final String file = yyResult.semanticValue();

                yyC = character(yyResult.index);
                if ('\"' == yyC) {
                  yyIndex = yyResult.index + 1;

                  yyOption1  = yyIndex;
                  yyOpValue1 = null;

                  yyBase = yyOption1;
                  yyC    = character(yyBase);
                  if (' ' == yyC) {
                    yyIndex = yyOption1 + 1;

                    yyC = character(yyIndex);
                    if ('1' == yyC) {
                      yyIndex = yyIndex + 1;
                      final String v$el$1 = " 1";

                      yyOption1  = yyIndex;
                      yyOpValue1 = v$el$1;
                    } else {
                      yyError = yyError.select("' 1' expected", yyBase);
                    }
                  } else {
                    yyError = yyError.select("' 1' expected", yyBase);
                  }
                  { // Start scope for f1.
                    final String f1 = yyOpValue1;

                    yyOpValue1 = null;

                    yyBase = yyOption1;
                    yyC    = character(yyBase);
                    if (' ' == yyC) {
                      yyIndex = yyOption1 + 1;

                      yyC = character(yyIndex);
                      if ('2' == yyC) {
                        yyIndex = yyIndex + 1;
                        final String v$el$2 = " 2";

                        yyOption1  = yyIndex;
                        yyOpValue1 = v$el$2;
                      } else {
                        yyError = yyError.select("' 2' expected", yyBase);
                      }
                    } else {
                      yyError = yyError.select("' 2' expected", yyBase);
                    }
                    { // Start scope for f2.
                      final String f2 = yyOpValue1;

                      yyOpValue1 = null;

                      yyBase = yyOption1;
                      yyC    = character(yyBase);
                      if (' ' == yyC) {
                        yyIndex = yyOption1 + 1;

                        yyC = character(yyIndex);
                        if ('3' == yyC) {
                          yyIndex = yyIndex + 1;
                          final String v$el$3 = " 3";

                          yyOption1  = yyIndex;
                          yyOpValue1 = v$el$3;
                        } else {
                          yyError = yyError.select("' 3' expected", yyBase);
                        }
                      } else {
                        yyError = yyError.select("' 3' expected", yyBase);
                      }
                      { // Start scope for f3.
                        final String f3 = yyOpValue1;

                        yyOpValue1 = null;

                        yyBase = yyOption1;
                        yyC    = character(yyBase);
                        if (' ' == yyC) {
                          yyIndex = yyOption1 + 1;

                          yyC = character(yyIndex);
                          if ('4' == yyC) {
                            yyIndex = yyIndex + 1;
                            final String v$el$4 = " 4";

                            yyOption1  = yyIndex;
                            yyOpValue1 = v$el$4;
                          } else {
                            yyError = yyError.select("' 4' expected", yyBase);
                          }
                        } else {
                          yyError = yyError.select("' 4' expected", yyBase);
                        }
                        { // Start scope for f4.
                          final String f4 = yyOpValue1;

                          yyPredResult = pLineTerminator(yyOption1);
                          yyError      = yyPredResult.select(yyError);
                          if (yyPredResult.hasValue()) {

                            final int lineNo = Integer.parseInt(line);
                            if (RELOCATE) setLocation(yyStart, file, lineNo-1, FIRST_COLUMN);
                            yyState.lineMarker(file, lineNo, f1, f2, f3, f4, location(yyStart));

                            yyValue = null;

                            return new SemanticValue(yyValue, yyOption1, yyError);
                          }
                        } // End scope for f4.
                      } // End scope for f3.
                    } // End scope for f2.
                  } // End scope for f1.
                }
              }
            }
          }
        }
      }

      // Nested alternative 2.

      yyRepetition1 = yyChoice1;
      while (true) {

        yyResult = pSpace(yyRepetition1);
        yyError  = yyResult.select(yyError, yyRepetition1);
        if (yyResult.hasValue()) {

          yyRepetition1 = yyResult.index;
          continue;
        }
        break;
      }
      { // Start scope for nested choice.

        final int yyChoice2 = yyRepetition1;

        // Nested alternative 1.

        yyC = character(yyChoice2);
        if (-1 != yyC) {
          yyIndex = yyChoice2 + 1;

          switch (yyC) {
          case 'p':
            {
              yyC = character(yyIndex);
              if (-1 != yyC) {
                yyIndex = yyIndex + 1;
                if ('r' == yyC) {

                  yyC = character(yyIndex);
                  if (-1 != yyC) {
                    yyIndex = yyIndex + 1;
                    if ('a' == yyC) {

                      yyC = character(yyIndex);
                      if (-1 != yyC) {
                        yyIndex = yyIndex + 1;
                        if ('g' == yyC) {

                          yyC = character(yyIndex);
                          if (-1 != yyC) {
                            yyIndex = yyIndex + 1;
                            if ('m' == yyC) {

                              yyC = character(yyIndex);
                              if (-1 != yyC) {
                                yyIndex = yyIndex + 1;
                                if ('a' == yyC) {

                                  yyC = character(yyIndex);
                                  if (-1 != yyC) {
                                    yyIndex = yyIndex + 1;
                                    if (' ' == yyC) {

                                      yyResult = pPragma(yyIndex);
                                      yyError  = yyResult.select(yyError);
                                      if (yyResult.hasValue()) {
                                        final String pragma = yyResult.semanticValue();

                                        yyPredResult = 
                                          pLineTerminator(yyResult.index);
                                        yyError      = 
                                          yyPredResult.select(yyError);
                                        if (yyPredResult.hasValue()) {

                                          yyState.pragma(pragma, location(yyStart));

                                          yyValue = null;

                                          return yyResult.createValue(yyValue, yyError);
                                        }
                                      }
                                    }
                                  }
                                }
                              }
                            }
                          }
                        }
                      }
                    }
                  }
                }
              }
            }
            break;

          case 'i':
            {
              yyC = character(yyIndex);
              if (-1 != yyC) {
                yyIndex = yyIndex + 1;
                if ('d' == yyC) {

                  yyC = character(yyIndex);
                  if (-1 != yyC) {
                    yyIndex = yyIndex + 1;
                    if ('e' == yyC) {

                      yyC = character(yyIndex);
                      if (-1 != yyC) {
                        yyIndex = yyIndex + 1;
                        if ('n' == yyC) {

                          yyC = character(yyIndex);
                          if (-1 != yyC) {
                            yyIndex = yyIndex + 1;
                            if ('t' == yyC) {

                              yyRepetition1 = yyIndex;
                              yyRepeated1   = false;
                              while (true) {

                                yyResult = pSpace(yyRepetition1);
                                yyError  = yyResult.select(yyError);
                                if (yyResult.hasValue()) {

                                  yyRepetition1 = yyResult.index;
                                  yyRepeated1   = true;
                                  continue;
                                }
                                break;
                              }

                              if (yyRepeated1) {

                                yyC = character(yyRepetition1);
                                if ('\"' == yyC) {
                                  yyIndex = yyRepetition1 + 1;

                                  yyResult = pFileName(yyIndex);
                                  yyError  = yyResult.select(yyError);
                                  if (yyResult.hasValue()) {
                                    final String s = yyResult.semanticValue();

                                    yyC = character(yyResult.index);
                                    if ('\"' == yyC) {
                                      yyIndex = yyResult.index + 1;

                                      yyPredResult = pLineTerminator(yyIndex);
                                      yyError      = 
                                        yyPredResult.select(yyError);
                                      if (yyPredResult.hasValue()) {

                                        yyState.ident(s, location(yyStart));

                                        yyValue = null;

                                        return new SemanticValue(yyValue, yyIndex, yyError);
                                      }
                                    }
                                  }
                                }
                              }
                            }
                          }
                        }
                      }
                    }
                  }
                }
              }
            }
            break;

          default:
            /* No match. */
          }
        }
      } // End scope for nested choice.
    }

    // Alternative 2.

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSpacing.LineNumber.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pLineNumber(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    int        yyRepetition1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyC = character(yyStart);
    if (-1 != yyC) {
      yyIndex = yyStart + 1;

      switch (yyC) {
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
      case '8':
      case '9':
        {
          yyRepetition1 = yyIndex;
          while (true) {

            yyC = character(yyRepetition1);
            if (-1 != yyC) {
              yyIndex = yyRepetition1 + 1;

              switch (yyC) {
              case '0':
              case '1':
              case '2':
              case '3':
              case '4':
              case '5':
              case '6':
              case '7':
              case '8':
              case '9':
                {
                  yyRepetition1 = yyIndex;
                  continue;
                }

              default:
                /* No match. */
              }
            }
            break;
          }

          yyValue = difference(yyStart, yyRepetition1);

          return new SemanticValue(yyValue, yyRepetition1, yyError);
        }

      default:
        /* No match. */
      }
    }

    // Done.
    yyError = yyError.select("line number expected", yyStart);
    return yyError;
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSpacing.FileName.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pFileName(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    int        yyRepetition1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    while (true) {

      final int yyChoice1 = yyRepetition1;

      // Nested alternative 1.

      yyC = character(yyChoice1);
      if (-1 != yyC) {
        yyIndex = yyChoice1 + 1;

        switch (yyC) {
        case '\\':
          {
            yyC = character(yyIndex);
            if (-1 != yyC) {
              yyIndex = yyIndex + 1;

              yyRepetition1 = yyIndex;
              continue;
            }
          }
          break;

        default:
          /* No match. */
        }
      }

      // Nested alternative 2.

      yyC = character(yyChoice1);
      if (-1 != yyC) {
        yyIndex = yyChoice1 + 1;

        switch (yyC) {
        case '\"':
        case '\\':
          /* No match. */
          break;

        default:
          {
            yyRepetition1 = yyIndex;
            continue;
          }
        }
      }
      break;
    }

    yyValue = difference(yyStart, yyRepetition1);

    return new SemanticValue(yyValue, yyRepetition1, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CSpacing.Pragma.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPragma(final int yyStart) throws IOException {
    int        yyC;
    int        yyIndex;
    int        yyRepetition1;
    String     yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyRepetition1 = yyStart;
    while (true) {

      yyC = character(yyRepetition1);
      if (-1 != yyC) {
        yyIndex = yyRepetition1 + 1;

        switch (yyC) {
        case '\n':
        case '\r':
          /* No match. */
          break;

        default:
          {
            yyRepetition1 = yyIndex;
            continue;
          }
        }
      }
      break;
    }

    yyValue = difference(yyStart, yyRepetition1);

    return new SemanticValue(yyValue, yyRepetition1, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CContext.TypedefContext.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pTypedefContext(final int yyStart) throws IOException {
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyState.typedef();

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CContext.ParameterContext.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pParameterContext(final int yyStart) throws IOException {
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyState.parameters();

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CContext.FunctionDeclaratorContext.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pFunctionDeclaratorContext(final int yyStart) 
    throws IOException {

    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyState.functionDeclarator();

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CContext.TypeSpecContext.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pTypeSpecContext(final int yyStart) throws IOException {
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyState.typeSpecifier();

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CContext.PushScope.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPushScope(final int yyStart) throws IOException {
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyState.pushScope();

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CContext.PopScope.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pPopScope(final int yyStart) throws IOException {
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyState.popScope();

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CContext.EnterStructure.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pEnterStructure(final int yyStart) throws IOException {
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyState.enterStructure();

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  /**
   * Parse nonterminal xtc.lang.CContext.ExitStructure.
   *
   * @param yyStart The index.
   * @return The result.
   * @throws IOException Signals an I/O error.
   */
  private Result pExitStructure(final int yyStart) throws IOException {
    Void       yyValue;
    ParseError yyError = ParseError.DUMMY;

    // Alternative 1.

    yyState.exitStructure();

    yyValue = null;

    return new SemanticValue(yyValue, yyStart, yyError);
  }

  // =========================================================================

  static {
    if (ASPECT) add(C_KEYWORDS, new String[] { "advice_before", "advice_after", "advice_intro" });
  }
  static {
    add(C_KEYWORDS, new String[] {
      "auto",       "break",      "case",       "char",
      "const",      "continue",   "default",    "do",
      "double",     "else",       "enum",       "extern",
      "float",      "for",        "goto",       "if",
      "int",        "long",       "register",   "return",
      "short",      "signed",     "sizeof",     "static",
      "struct",     "switch",     "typedef",    "union",
      "unsigned",   "void",       "volatile",   "while"
    });
    
    if (C99) add(C_KEYWORDS, new String[] {
      "_Bool",      "_Complex",   "inline",
      "restrict"
    });
    
    if (GCC) add(C_KEYWORDS, new String[] {
      "__alignof",   "__alignof__",
      "asm",         "__asm",         "__asm__",
      "__attribute", "__attribute__",
      "__builtin_offsetof",
      "__builtin_types_compatible_p",
      "__builtin_va_arg",             "__builtin_va_list",
      "__complex__",
      "__const",     "__const__",
      "__extension__",
      "__inline",    "__inline__",
      "__label__",
      "__restrict",  "__restrict__",
      "__signed",    "__signed__",
      "__thread",
      "typeof",      "__typeof",      "__typeof__",
      "__volatile",  "__volatile__"
    });
    
  }

  // =========================================================================

  /**
   * Get the specified text.
   *
   * @param s The text.
   * @return The text.
   */
  protected static final String toText(String s) {
    return s;
  }

  // =========================================================================

  /**
   * Add the specified values to the specified set.
   *
   * @param set The set.
   * @param values The new values.
   */
  protected static final <T> void add(Set<T> set, T[] values) {
    for (T v : values) set.add(v);
  }

  /**
   * Check whether the specified set contains the specified value.
   *
   * @param set The set.
   * @param value The value.
   * @return <code>true</code> if the set contains the value.
   */
  protected static final <T> boolean contains(Set<T> set, T value) {
    return set.contains(value);
  }

  // =========================================================================

  /**
   * Parse the specified files.
   *
   * @param args The file names.
   */
  public static void main(String[] args) {
    if ((null == args) || (0 == args.length)) {
      System.err.println("Usage: <file-name>+");

    } else {
      for (int i=0; i<args.length; i++) {
        System.err.println("Processing " + args[i] + " ...");

        Reader     in = null;
        try {
          in          = new BufferedReader(new FileReader(args[i]));
          C4Parser p  = 
            new C4Parser(in, args[i], (int)new File(args[i]).length());
          Result   r  = p.pTranslationUnit(0);

          if (r.hasValue()) {
            SemanticValue v = (SemanticValue)r;

            if (v.value instanceof Node) {
              Printer ptr = new
                Printer(new BufferedWriter(new OutputStreamWriter(System.out)));
              ptr.format((Node)v.value).pln().flush();
            } else {
              System.out.println(v.value.toString());
            }

          } else {
            ParseError err = (ParseError)r;
            if (-1 == err.index) {
              System.err.println("  Parse error");
            } else {
              System.err.println("  " + p.location(err.index) + ": " + err.msg);
            }
          }

        } catch (Throwable x) {
          while (null != x.getCause()) {
            x = x.getCause();
          }
          x.printStackTrace();
        } finally {
          try {
            in.close();
          } catch (Throwable x) {
            /* Ignore. */
          }
        }
      }
    }
  }

}
