Guint JBIG2HuffmanDecoder::readBit() {
  if (bufLen == 0) {
    buf = str->getChar();
    bufLen = 8;
  }
  --bufLen;
  return (buf >> bufLen) & 1;
}

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.