blit.m in module back

[Anibal Rindisbacher]

Hi, me again. I try to understand the code in back/Source/art/blit.m, I focus in warnings now, the line in MPRE(run_opaque) of that file:

unsigned int v;
unsigned short *dst = (unsigned short *)ri->dst;

COPY_ASSEMBLE_PIXEL(v, ri->r, ri->g, ri->b)
v = v + (v << 16);
if (((int)dst&2) && num)
{
      *dst++ = v;
      num--;
}

.....

in the if statement, verify that the bit 31st was 1, do you sure you want to do that?.