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

# Makefile to build the SDL library

INCLUDE = -I./include
CFLAGS  = -g -O2 $(INCLUDE)
AR	= ar
RANLIB	= ranlib

CONFIG_H = include/SDL_config.h
TARGET  = libSDL.a
SOURCES = \
	src/*.c \
	src/audio/*.c \
	src/cdrom/*.c \
	src/cpuinfo/*.c \
	src/events/*.c \
	src/file/*.c \
	src/joystick/*.c \
	src/stdlib/*.c \
	src/thread/*.c \
	src/timer/*.c \
	src/video/*.c \
	src/audio/dummy/*.c \
	src/video/dummy/*.c \
	src/joystick/dummy/*.c \
	src/cdrom/dummy/*.c \
	src/thread/generic/*.c \
	src/timer/dummy/*.c \
	src/loadso/dummy/*.c \

OBJECTS = $(shell echo $(SOURCES) | sed -e 's,\.c,\.o,g')

all: $(TARGET)

$(TARGET): $(CONFIG_H) $(OBJECTS)
	$(AR) crv $@ $^
	$(RANLIB) $@

$(CONFIG_H):
	cp $(CONFIG_H).default $(CONFIG_H)

clean:
	rm -f $(TARGET) $(OBJECTS)