inline int JBIG2Bitmap::nextPixel(JBIG2BitmapPtr *ptr) {
  int pix;

  if (!ptr->p) {
    pix = 0;
  } else if (ptr->x < 0) {
    ++ptr->x;
    pix = 0;
  } else {
    pix = (*ptr->p >> ptr->shift) & 1;
    if (++ptr->x == w) {
      ptr->p = NULL;
    } else if (ptr->shift == 0) {
      ++ptr->p;
      ptr->shift = 7;
    } else {
      --ptr->shift;
    }
  }
  return pix;
}

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