[FFmpeg-user] how to build ffmpeg with -O0 instead of -O1

[qw]

Hi,
 
I want to build ffmpeg without optimization options, which means compiling flags uses O0 instead of O1-O3. I use the following command to build ffmpeg, where O1 is used in config.mak.
 
./configure --enable-debug --disable-optimizations ......

I want to disable all optimization options to debug ffmpeg/ffmpeg_g program. If I change optimization options in config.mak, i.e. using O0 instead of O1, there will be some error messages during the building process:
 
libavutil/libavutil.a(cpu.o): In function `av_get_cpu_flags':
/export/qiang/sourceCode/ffmpeg-2.8.3/libavutil/cpu.c:82: undefined reference to `ff_get_cpu_flags_aarch64'
/export/qiang/sourceCode/ffmpeg-2.8.3/libavutil/cpu.c:84: undefined reference to `ff_get_cpu_flags_arm'
/export/qiang/sourceCode/ffmpeg-2.8.3/libavutil/cpu.c:86: undefined reference to `ff_get_cpu_flags_ppc'

How to build ffmpeg with O0 option?
 
B.R.
 
Andrew