title: FFmpeg seems to be version conflict
body: <p>I am using git version of ffmpeg( renewed after old version succesful using) , when i try to compile my project i get</p>
  
  <pre><code> /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_subpacket':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:376: undefined reference to `swr_is_initialized'
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_frame':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:222: undefined reference to `swr_is_initialized'
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_init_resample':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:163: undefined reference to `swr_init'
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:169: undefined reference to `swr_convert'
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_frame':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:236: undefined reference to `swr_convert'
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_flush_resample':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:117: undefined reference to `swr_convert'
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_subpacket':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:408: undefined reference to `swr_close'
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_flush':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:557: undefined reference to `swr_close'
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_close':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:579: undefined reference to `swr_free'
  /usr/local/lib/libavcodec.a(opusdec.o): In function `opus_decode_init':
  /home/user/projects/ffmpleglast/ffmpeg/libavcodec/opusdec.c:629: undefined reference to `swr_alloc'
  </code></pre>
  
  <p>Seems to be version conflict? but how to delete wrong libs? they seem to be todays build.</p>
  
  <pre><code>ls -l /usr/local/lib
  -rw-r--r-- 1 root root  136509684 may   29 14:47 libavcodec.a
  -rw-r--r-- 1 root root    1853574 may   29 14:47 libavdevice.a
  -rw-r--r-- 1 root root    9689456 may   29 14:47 libavfilter.a
  -rw-r--r-- 1 root root   46282270 may   29 14:47 libavformat.a
  -rw-r--r-- 1 root root    2092250 may   29 14:47 libavutil.a
  -rw-r--r-- 1 root root      67942 may   12 11:29 libBasicUsageEnvironment.a
  -rw-r--r-- 1 root root    2200164 apr.  10 10:11 libfftw3.a
  -rwxr-xr-x 1 root root        872 apr.  10 10:11 libfftw3.la
  -rw-r--r-- 1 root root      94188 may   12 11:29 libgroupsock.a
  -rw-r--r-- 1 root root    2236084 may   12 11:29 libliveMedia.a
  -rw-r--r-- 1 root root     546506 may   29 14:47 libswresample.a
  -rw-r--r-- 1 root root    4813716 may   29 14:47 libswscale.a
  -rw-r--r-- 1 root root      14588 may   12 11:29 libUsageEnvironment.a
  </code></pre>