[Libav-user] Error while linking

[Paul B Mahol]

On 9/18/15, gaurav mishra <gauravmishra.itbhu at gmail.com> wrote:
> Hi,
> I have written a app using ffmpeg's library and am able to compile and run
> it on my mac (slighly older version of ffmpeg installed). But when i am
> trying to build the code on ubuntu machine i am getting some errors
> few of them being
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavformat/rtmpproto.c:1087: undefined
> reference to `inflate'
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavformat/rtmpproto.c:1105: undefined
> reference to `inflateEnd'
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavformat/rtmpproto.c:1105: undefined
> reference to `inflateEnd'
>
> /usr/local/lib/libavformat.a(swfdec.o): In function `swf_read_packet':
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavformat/swfdec.c:358: undefined
> reference to `uncompress'
>
> /usr/local/lib/libavformat.a(swfdec.o): In function `swf_read_header':
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavformat/swfdec.c:147: undefined
> reference to `inflateInit_'
>
> /usr/local/lib/libavformat.a(swfdec.o): In function `zlib_refill':
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavformat/swfdec.c:115: undefined
> reference to `inflate'
>
> /usr/local/lib/libavformat.a(swfdec.o): In function `swf_read_close':
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavformat/swfdec.c:523: undefined
> reference to `inflateEnd'
>
> /usr/local/lib/libavcodec.a(cscd.o): In function `decode_frame':
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavcodec/cscd.c:91: undefined
> reference to `uncompress'
>
> /usr/local/lib/libavcodec.a(dxa.o): In function `decode_frame':
>
> /home/ubuntu/ffmpeg_sources/ffmpeg/libavcodec/dxa.c:250: undefined
> reference to `uncompress'
>
>
> the list of undefined reference errors is quite huge.
>
> the command which i am using to link looks like this--
>
> g++  file1.o file2.o file3.o  -L/usr/lib/x86_64-linux-gnu -L/usr/local/lib
> -L/home/ubuntu/casablanca/Release/build.release/Binaries -lpthread
> -lavutil  -lavformat
> -lavcodec -lavfilter -lboost_system -lboost_thread -lboost_chrono -lcpprest
> -lswscale -o final


Hmm try linking with -lzlib too.

> the issue seems to be related to order of linking. is there a mistake in
> order in which i am linking the libs.
> PS - lpthread was not required when i was building on my mac.
>
> following is the output of ffmpeg -i
>
> ffmpeg version N-75410-g58fe57d Copyright (c) 2000-2015 the FFmpeg
> developers
>
>   built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04)
>
>   configuration: --enable-gpl --enable-libfdk-aac --enable-libx264
> --enable-libopus --enable-nonfree
>
>   libavutil      55.  2.100 / 55.  2.100
>
>   libavcodec     57.  3.100 / 57.  3.100
>
>   libavformat    57.  2.100 / 57.  2.100
>
>   libavdevice    57.  0.100 / 57.  0.100
>
>   libavfilter     6.  5.100 /  6.  5.100
>
>   libswscale      4.  0.100 /  4.  0.100
>
>   libswresample   2.  0.100 /  2.  0.100
>
>   libpostproc    54.  0.100 / 54.  0.100
>