title: vlc 3.0 ./configure gives "Missing libav or FFmpeg" despite I have them
body: <p>I am trying to build the most recent development version of vlc-3.0 (git cloned) from source, but running <code>./configure</code> gives me the following error:</p>
  
  <pre><code>configure: error: Missing libav or FFmpeg
  </code></pre>
  
  <p>That is despite I have built from source and installed a fresh ffmpeg-3.2.2 with the following configuration including --enable-shared (see below). Also, in my /usr/lib directory there is a library libavcodec.a , libavcodec.so.57.64.101 with symbolic links to it libavcodec.so and libavcodec.so.57</p>
  
  <p>Just looked at <a href="https://github.com/videolan/vlc/blob/master/configure.ac" rel="nofollow noreferrer">https://github.com/videolan/vlc/blob/master/configure.ac</a> source code, it requires a libavcodec >=57.16.0 from libav or >=57.37.100 from ffmpeg, and 57.64.101 satisfies that requirement so still can't understand what is wrong. </p>
  
  <p><strong>Maybe I need to pass some additional flag to vlc-3.0 to force it to notice my libavcodec library? If yes, what flags should I try?</strong></p>
  
  <p>ffmpeg configure options (just in case): </p>
  
  <pre><code>--prefix=/usr --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --disable-libebur128 --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librubberband --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libiec61883 --enable-libopencv --enable-frei0r --enable-libx264 --enable-chromaprint --enable-shared
  </code></pre>