Program: 12300
Project: 12300
Buggy source:
/** 
 * This is a utility routine which figures out what kind(s) of symbol a given string could represent. At entry: s, length_of_s represent the string. At exit: possible_xxx is set to TRUE/FALSE to indicate whether the given string could represent that kind of symbol; rereadable is set to TRUE indicating whether the lexer would read the given string as a symbol with exactly the same name (as opposed to treating it as a special lexeme like "+", changing upper to lower case, etc. <p>lexer.cpp:1225:determine_possible_symbol_types_for_string
 */
public static PossibleSymbolTypes determine_possible_symbol_types_for_string(String s){
  PossibleSymbolTypes p=new PossibleSymbolTypes();
  if (s.length() == 0) {
    return p;
  }
  if (Lexer.number_starters[s.charAt(0)]) {
    try {
      Integer.parseInt(s);
      p.possible_ic=true;
    }
 catch (    NumberFormatException e) {
    }
    try {
      Float.parseFloat(s);
      p.possible_fc=s.indexOf('.') != -1;
    }
 catch (    NumberFormatException e) {
    }
  }
  for (int i=0; i < s.length(); ++i) {
    if (!Lexer.constituent_char[s.charAt(i)]) {
      return p;
    }
  }
  p.possible_sc=true;
  if ((s.charAt(0) == '<') && (s.charAt(s.length() - 1) == '>')) {
    p.possible_var=true;
  }
  boolean rereadability_questionable=false;
  boolean rereadability_dead=false;
  for (int i=0; i < s.length(); i++) {
    char ch=s.charAt(i);
    if (Character.isLowerCase(ch) || Character.isDigit(ch))     continue;
    if (Character.isUpperCase(ch)) {
      rereadability_dead=true;
      break;
    }
    rereadability_questionable=true;
  }
  if (!rereadability_dead) {
    if ((!rereadability_questionable) || (s.length() >= LENGTH_OF_LONGEST_SPECIAL_LEXEME) || ((s.length() == 1) && (s.charAt(0) == '*')))     p.rereadable=true;
  }
  if (Character.isLetter(s.charAt(0))) {
    int i=1;
    while (i < s.length() && Character.isDigit(s.charAt(i))) {
      ++i;
    }
    p.possible_id=i == s.length();
  }
  return p;
}

Fixed version (ground truth):
/** 
 * This is a utility routine which figures out what kind(s) of symbol a given string could represent. At entry: s, length_of_s represent the string. At exit: possible_xxx is set to TRUE/FALSE to indicate whether the given string could represent that kind of symbol; rereadable is set to TRUE indicating whether the lexer would read the given string as a symbol with exactly the same name (as opposed to treating it as a special lexeme like "+", changing upper to lower case, etc. <p>lexer.cpp:1225:determine_possible_symbol_types_for_string
 */
public static PossibleSymbolTypes determine_possible_symbol_types_for_string(String s){
  PossibleSymbolTypes p=new PossibleSymbolTypes();
  if (s.length() == 0) {
    return p;
  }
  if (Lexer.number_starters[s.charAt(0)]) {
    try {
      Integer.parseInt(s);
      p.possible_ic=true;
    }
 catch (    NumberFormatException e) {
    }
    try {
      Float.parseFloat(s);
      p.possible_fc=s.indexOf('.') != -1;
    }
 catch (    NumberFormatException e) {
    }
  }
  for (int i=0; i < s.length(); ++i) {
    if (!isConstituentChar(s.charAt(i))) {
      return p;
    }
  }
  p.possible_sc=true;
  if ((s.charAt(0) == '<') && (s.charAt(s.length() - 1) == '>')) {
    p.possible_var=true;
  }
  boolean rereadability_questionable=false;
  boolean rereadability_dead=false;
  for (int i=0; i < s.length(); i++) {
    char ch=s.charAt(i);
    if (Character.isLowerCase(ch) || Character.isDigit(ch))     continue;
    if (Character.isUpperCase(ch)) {
      rereadability_dead=true;
      break;
    }
    rereadability_questionable=true;
  }
  if (!rereadability_dead) {
    if ((!rereadability_questionable) || (s.length() >= LENGTH_OF_LONGEST_SPECIAL_LEXEME) || ((s.length() == 1) && (s.charAt(0) == '*')))     p.rereadable=true;
  }
  if (Character.isLetter(s.charAt(0))) {
    int i=1;
    while (i < s.length() && Character.isDigit(s.charAt(i))) {
      ++i;
    }
    p.possible_id=i == s.length();
  }
  return p;
}