fbCombineXorC (CARD32 *dest, CARD32 *src, CARD32 *mask, int width)
{
    int i;

    for (i = 0; i < width; ++i) {
        CARD32 d = READ(dest + i);
        CARD32 s = READ(src + i);
        CARD32 m = READ(mask + i);
        CARD32 ad;
        CARD16 as = ~d >> 24;

	fbCombineMaskC (&s, &m);

	ad = ~m;

        FbByteAddMulC(d, ad, s, as);
        WRITE(dest + i, d);
    }
}

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