Fixed bug #1111

kwm@rainbow-runner.nl      2011-01-30 06:28:27 PST

Created attachment 562 [details]
Build fix with clang.

When building sdl 1.2.14 with the Clang compiler http://clang.llvm.org .
The build fails in src/video/mmx.h with the following error:

--------------------------------------------------
./src/video/SDL_RLEaccel.c:831:5: error: invalid operand for instruction
    CHOOSE_BLIT(RLECLIPBLIT, alpha, fmt);
    ^
./src/video/SDL_RLEaccel.c:831:17: note: instantiated from:
    CHOOSE_BLIT(RLECLIPBLIT, alpha, fmt);
                ^
./src/video/SDL_RLEaccel.c:831:5: note: instantiated from:
    CHOOSE_BLIT(RLECLIPBLIT, alpha, fmt);
    ^
./src/video/SDL_RLEaccel.c:647:23: note: instantiated from:
                                blitter(2, Uint8, ALPHA_BLIT16_565MMX); \
                                                  ^
./src/video/SDL_RLEaccel.c:282:4: note: instantiated from:
          movq_r2m(mm3, *dstp);                         \
          ^
In file included from ./src/video/SDL_RLEaccel.c:99:
./src/video/mmx.h:379:28: note: instantiated from:
#define movq_r2m(reg, var)      mmx_r2m(movq, reg, var)
                                ^
<scratch space>:192:1: note: instantiated from:
"movq"
^
<inline asm>:1:2: note: instantiated into assembly here
        movq %mm3, %dx
        ^
--------------------------------------------------

According to the clang developers this is a invalid inline assembly.
Using the attached patch from the last commit in the below bug report fixes the
compile.
More details from: http://llvm.org/bugs/show_bug.cgi?id=6730

src/video/mmx.h

@@ -293,7 +293,7 @@ mmx_ok(void)
 
 #define	mmx_r2m(op, reg, mem) \
 	__asm__ __volatile__ (#op " %%" #reg ", %0" \
-			      : "=X" (mem) \
+			      : "=m" (mem) \
 			      : /* nothing */ )
 
 #define	mmx_r2r(op, regs, regd) \