fbStore_x1b5g5r5 (FbBits *bits, const CARD32 *values, int x, int width, miIndexedPtr indexed)
{
    int i;
    CARD16  *pixel = ((CARD16 *) bits) + x;
    for (i = 0; i < width; ++i) {
        Split(READ(values + i));
        WRITE(pixel++, ((b << 7) & 0x7c00) |
	      ((g << 2) & 0x03e0) |
	      ((r >> 3)         ));
    }
}

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