When compiling mesa and xorg-server (in the same file in fact) and using -march=k6-3 I got an assembly error, that not occurs if using (for proximity to my type of cpu) -march=pentium-mmx I've got the same error also in two other packages: imagemagick and sdl_image.
Steps to reproduce: ------------------ 1) compile the Mesa-6.4.2/src/mesa/main/texcompress_fxt1.c with the following comand line: gcc -c -I../../include -I../../src/mesa -I../../src/mesa/main -I../../src/mesa/glapi -I../../src/mesa/math -I../../src/mesa/tnl -I../../src/mesa/shader -I../../src/mesa/shader/grammar -I../../src/mesa/shader/slang -I../../src/mesa/shader/slang/OSDependent/Linux -I../../src/mesa/shader/slang/OGLCompilersDLL -I../../src/mesa/swrast -I../../src/mesa/swrast_setup -Wall -O2 -march=k6-3 -fomit-frame-pointer -pipe -fPIC -m32 -D_POSIX_SOURCE -D_POSIX_C_SOURCE=199309L -D_SVID_SOURCE -D_BSD_SOURCE -D_GNU_SOURCE -DPTHREADS -DUSE_EXTERNAL_DXTN_LIB=1 -DIN_DRI_DRIVER -DGLX_DIRECT_RENDERING -DHAVE_ALIAS -DDEFAULT_DRIVER_DIR='"/usr/lib/xorg/modules/dri"' -DUSE_X86_ASM -DUSE_MMX_ASM -DUSE_3DNOW_ASM -DUSE_SSE_ASM -std=c99 -ffast-math main/texcompress_fxt1.c -o main/texcompress_fxt1.o -Wall Results: ------- The output of the compiler is {entrada estándar}: Mensajes del ensamblador: {entrada estándar}:1385: Error: el valor de ffffffffffffff7e es demasiado grande para el campo de 1 bytes en 00000000000010d5 The english translation I think is like: {standard input}: Assembler messages: {standard input}:1385: Error: value of ffffffffffffff7e too large for field of 1 bytes at 00000000000010d5 Build Date & Platform: --------------------- 2006-03-24 Linux (kernel 2.6.15-gentoo-r1 ) i586 AMD-K6-III(tm) 3D+ Processor -- Summary: compilation errors in mesa and xorg-server with - march=k6-3 Product: gcc Version: 3.4.5 Status: UNCONFIRMED Severity: normal Priority: P3 Component: other AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: agathos at fobos dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26856