Hi all I just ran into this compile time error and I thought I would report it here. I am building on MacOSX 10.5 with gcc 4.0.1. If I should have use the bug reporter, please let me know, $ gcc -v Using built-in specs. Target: i686-apple-darwin9 Configured with: /var/tmp/gcc/gcc-5493~1/src/configure --disable-checking -enable-werror --prefix=/usr --mandir=/share/man --enable-languages=c,objc,c++,obj-c++ --program-transform-name=/^[cg][^.-]*$/s/$/-4.0/ --with-gxx-include-dir=/include/c++/4.0.0 --with-slibdir=/usr/lib --build=i686-apple-darwin9 --with-arch=apple --with-tune=generic --host=i686-apple-darwin9 --target=i686-apple-darwin9 Thread model: posix gcc version 4.0.1 (Apple Inc. build 5493) configured like so: /Users/mo/Development/ffmpeg_head/ffmpeg/configure \ --prefix=/Users/mo/Development/install/ffmpeg_head \ --disable-shared \ --enable-static \ --enable-gpl \ --disable-ffserver \ --disable-optimizations \ --disable-stripping \

configure.out 2>&1

gcc -DHAVE_AV_CONFIG_H -I. -I"/Users/mo/Development/ffmpeg_head/ffmpeg" -D_ISOC99_S OURCE -D_POSIX_C_SOURCE=200112 -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -DPIC -st d=c99 -fPIC -g -Wdeclaration-after-statement -Wall -Wno-switch -Wdisabled-optimizat ion -Wpointer-arith -Wredundant-decls -Wno-pointer-sign -Wcast-qual -Wwrite-strings -Wundef -fno-math-errno -fno-tree-vectorize -MMD -MF libavcodec/x86/dsputil _mmx.d -MT libavcodec/x86/dsputil_mmx.o -c -o libavcodec/x86/dsputil_mmx.o /Users/m o/Development/ffmpeg_head/ffmpeg/libavcodec/x86/dsputil_mmx.c /Users/mo/Development/ffmpeg_head/ffmpeg/libavcodec/x86/dsputil_mmx.c: In function ?transpose4x4?: /Users/mo/Development/ffmpeg_head/ffmpeg/libavcodec/x86/dsputil_mmx.c:726: error: can't find a register in class ?GENERAL_REGS? while reloading ?asm? make: *** [libavcodec/x86/dsputil_mmx.o] Error 1 This sounds like some sort of register issue, found this post which might be related: http://gcc.gnu.org/ml/gcc-help/2007-04/msg00205.html passing --disable-asm to configure got it building. cheers Mo DeJong