[FFmpeg-user] No compiled with -fPIC for libavcodec/aarch64/vp9mc_16bpp_neon.S

[Peng Gao]

Hi guys,

  I compiled ffmpeg(4.3.1) with the following configuration on Linux:
 ./configure --prefix= ~/wk/install/ffmpeg --enable-pic  --disable-ffplay
--disable-ffprobe  --enable-static --enable-gpl
--enable-libx264 --extra-cflags="-fpic"

ffmpeg was compiled successfully.

 There are some link errors when I compiled the OpenCV(4.6.0)  With the
following configuration :
cmake .. -D WITH_OPENCL=ON -D WITH_FFMPEG=ON  -D CMAKE_BUILD_TYPE=Release ,

 following is the error:
 /ffmpeg/lib/libavcodec.a(vp9mc_16bpp_neon.o): relocation
R_AARCH64_ADR_PREL_PG_HI21 against symbol `ff_vp9_subpel_filters' which may
bind externally can not be used when making a shared object; recompile with
-fPIC
/ffmpeg/lib/libavcodec.a(vp9mc_16bpp_neon.o): In function
`ff_vp9_avg_sharp4_v_12_neon':
libavcodec/aarch64/vp9mc_16bpp_neon.S:606:(.text+0x230c): dangerous
relocation: unsupported relocation.

It shows ffmpeg should be compiled with -fPIC,  this is also enabled in the
configuration when compiling the ffmpeg , so I don't know why it is and I
try to get help from the community .


Thanks,
Jerry