From: Gabriel Gambetta To: SDL Mailing List <sdl@libsdl.org> Date: Fri, 17 Nov 2006 00:39:29 -0200 Subject: [SDL] Alpha blending bug - fixed? It turns out mm5 never got the correct value. This failed : [...] "movd %1, %%mm5\n\t" : : "m" (amask), "m" (sf->Ashift) ); mm5 got 0xFF000018 instead of 0x00000018. However I did this : Uint32 ashift = sf->Ashift; [...] "movd %1, %%mm5\n\t" : : "m" (amask), "m" (ashift) ); and everything worked fine. The only thing I could find out was that ashift is 32-bit aligned but sf->Ashift isn't: printf("ashift %8X [%d]\n", &ashift, (int)(&ashift) % 4); printf("sf->Ashift %8X [%d]\n", &sf->Ashift, (int)(&sf->Ashift) % 4); ashift at BFF0E0C4 [0] sf->Ashift at 08AFB9CD [1] Could this be the problem? If it is, the fix is extremely trivial. Should I submit a patch? --Gabriel

#!/bin/sh
#
# libtool assumes that the compiler can handle the -fPIC flag
# This isn't always true (for example, nasm can't handle it)
command=""
while [ $# -gt 0 ]; do
    case "$1" in
        -?PIC)
            # Ignore -fPIC and -DPIC options
            ;;
        -fno-common)
            # Ignore -fPIC and -DPIC options
            ;;
        *)
            command="$command $1"
            ;;
    esac
    shift
done
echo $command
exec $command