Program: 161798
Project: 161798
Buggy source:
/** 
 * Find offset match either in an array of bytes or chars, which ever is not null.
 */
protected String findOffsetMatch(TestInfo info,int startOffset,MutableOffset mutableOffset,byte[] bytes,char[] chars,int maxPos){
  int targetPos=startOffset;
  boolean lastMagicCompactWhitespace=false;
  for (int magicPos=0; magicPos < info.pattern.length(); magicPos++) {
    char magicCh=info.pattern.charAt(magicPos);
    boolean lastChar=(magicPos == info.pattern.length() - 1);
    if (targetPos >= maxPos) {
      return null;
    }
    char targetCh;
    if (bytes == null) {
      targetCh=chars[targetPos];
    }
 else {
      targetCh=charFromByte(bytes,targetPos);
    }
    targetPos++;
    if (info.operator.doTest(targetCh,magicCh,lastChar)) {
      if (info.compactWhiteSpace) {
        lastMagicCompactWhitespace=Character.isWhitespace(magicCh);
      }
      continue;
    }
    if ((lastMagicCompactWhitespace || info.optionalWhiteSpace) && Character.isWhitespace(targetCh)) {
      do {
        if (targetPos >= maxPos) {
          break;
        }
        if (bytes == null) {
          targetCh=chars[targetPos];
        }
 else {
          targetCh=charFromByte(bytes,targetPos);
        }
        targetPos++;
      }
 while (Character.isWhitespace(targetCh));
      if (info.operator.doTest(targetCh,magicCh,lastChar)) {
        if (info.compactWhiteSpace) {
          lastMagicCompactWhitespace=Character.isWhitespace(magicCh);
        }
        continue;
      }
    }
    if (info.caseInsensitive && Character.isLowerCase(magicCh)) {
      if (info.operator.doTest(Character.toLowerCase(targetCh),magicCh,lastChar)) {
        continue;
      }
    }
    return null;
  }
  if (bytes == null) {
    chars=Arrays.copyOfRange(chars,startOffset,targetPos);
  }
 else {
    chars=new char[targetPos - startOffset];
    for (int i=0; i < chars.length; i++) {
      chars[i]=charFromByte(bytes,startOffset + i);
    }
  }
  mutableOffset.offset=targetPos;
  return new String(chars);
}

Fixed version (ground truth):
/** 
 * Find offset match either in an array of bytes or chars, which ever is not null.
 */
protected String findOffsetMatch(TestInfo info,int startOffset,MutableOffset mutableOffset,final byte[] bytes,final char[] chars,final int maxPos){
  if (startOffset < 0) {
    return null;
  }
  int targetPos=startOffset;
  boolean lastMagicCompactWhitespace=false;
  for (int magicPos=0; magicPos < info.pattern.length(); magicPos++) {
    char magicCh=info.pattern.charAt(magicPos);
    boolean lastChar=(magicPos == info.pattern.length() - 1);
    if (targetPos >= maxPos) {
      return null;
    }
    char targetCh;
    if (bytes == null) {
      targetCh=chars[targetPos];
    }
 else {
      targetCh=charFromByte(bytes,targetPos);
    }
    targetPos++;
    if (info.operator.doTest(targetCh,magicCh,lastChar)) {
      if (info.compactWhiteSpace) {
        lastMagicCompactWhitespace=Character.isWhitespace(magicCh);
      }
      continue;
    }
    if ((lastMagicCompactWhitespace || info.optionalWhiteSpace) && Character.isWhitespace(targetCh)) {
      do {
        if (targetPos >= maxPos) {
          break;
        }
        if (bytes == null) {
          targetCh=chars[targetPos];
        }
 else {
          targetCh=charFromByte(bytes,targetPos);
        }
        targetPos++;
      }
 while (Character.isWhitespace(targetCh));
      if (info.operator.doTest(targetCh,magicCh,lastChar)) {
        if (info.compactWhiteSpace) {
          lastMagicCompactWhitespace=Character.isWhitespace(magicCh);
        }
        continue;
      }
    }
    if (info.caseInsensitive && Character.isLowerCase(magicCh)) {
      if (info.operator.doTest(Character.toLowerCase(targetCh),magicCh,lastChar)) {
        continue;
      }
    }
    return null;
  }
  char[] resultChars;
  if (bytes == null) {
    resultChars=Arrays.copyOfRange(chars,startOffset,targetPos);
  }
 else {
    resultChars=new char[targetPos - startOffset];
    for (int i=0; i < resultChars.length; i++) {
      resultChars[i]=charFromByte(bytes,startOffset + i);
    }
  }
  mutableOffset.offset=targetPos;
  return new String(resultChars);
}