编译选项：./configure —-cc=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang --prefix=/Users/lushengpeng/Desktop/ffmpeg_64 --enable-cross-compile --sysroot=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.1.sdk --target-os=darwin--enable-libx264 --enable-gpl --extra-cflags=-I/Users/lushengpeng/Desktop/h264_64/include --extra-ldflags=-L/Users/lushengpeng/Desktop/h264_64/lib --enable-decoder=h264 --enable-encoder=libx264 --extra-cflags='-arch arm64' --extra-ldflags='-arch arm64 -L/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.1.sdk' --arch=arm --cpu=cortex-a15 --enable-pic --disable-asm —-logfile=/Users/lushengpeng/Desktop
提示信息：Unknown option "—-cc=“/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang”".
参考这篇说明：
http://stackoverflow.com/questions/22678938/error-compiling-x264-on-mac-os-x
把：
# CFLAGS="$CFLAGS -falign-loops=16"
改成
CFLAGS="$CFLAGS"
后，可以解决找不到编译器的问题。但我使用xcode5.1.1版本，又会遇到下面问题(暂时还无法解决，用xcode5.0.x版本编译这2个问题都不会遇到)：
You can run 'make' or 'make fprofiled' now.
cat common/opencl/x264-cl.h common/opencl/bidir.cl common/opencl/downscale.cl common/opencl/intra.cl common/opencl/motionsearch.cl common/opencl/subpel.cl common/opencl/weightp.cl | perl ./tools/cltostr.pl x264_opencl_source > common/oclobj.h
gcc -Wshadow -O3 -fno-fast-math -Wall -I. -I. --sysroot=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.1.sdk -w -O2 -arch armv7 -mfpu=neon -mfloat-abi=softfp -no-integrated-as -std=gnu99 -fPIC -fomit-frame-pointer -fno-tree-vectorize -c -o x264.o x264.c
/var/folders/q1/4qhl6c750b91th89c8yq89180000gq/T/x264-be6961.s:116:']' expected -- `vst1.64 {d8,d9},[r4:128]'
/var/folders/q1/4qhl6c750b91th89c8yq89180000gq/T/x264-be6961.s:1137:']' expected -- `vld1.64 {d8,d9},[r4:128]'
clang: error: assembler command failed with exit code 1 (use -v to see invocation)
make: *** [x264.o] Error 1