Build fail: tries to use codeparsers although it didn't find them

[eero-t]

Setup:

• Ubuntu 18.04
• Latest Open Source MediaSDK built from Git
• Git version of gstreamer-media-SDK

Problem:

• Build notices that optional gstreamer-codecparsers-1.0 dependency is missing, and then it tries to use it anyway:

  cmake -DCMAKE_INSTALL_PREFIX=/opt/install/Custom_4159 -DCMAKE_INSTALL_LIBDIR=lib -G Ninja -DWITH_X11=ON -DWITH_WAYLAND=ON -DMFX_MPEG2_ENCODER=ON  gstreamer-media-sdk/
  ...
  -- Checking for module 'gstreamer-codecparsers-1.0'
  --   No package 'gstreamer-codecparsers-1.0' found
  ...
  [1/52] Building C object CMakeFiles/gstmfx.dir/gst-libs/mfx/gstmfxdecoder.c.o
  FAILED: CMakeFiles/gstmfx.dir/gst-libs/mfx/gstmfxdecoder.c.o 
  /usr/bin/cc -DHAVE_GST_GL_LIBS -DHAVE_XCBDRI3 -DHAVE_XCBPRESENT -DHAVE_XKBLIB -DHAVE_XRANDR -DHAVE_XRENDER -DMFX_DECODER -DMFX_H264_ENCODER -DMFX_H265_ENCODER -DMFX_JPEG_ENCODER -DMFX_MPEG2_ENCODER -DMFX_SINK -DMFX_SINK_BIN -DMFX_VC1_PARSER -DMFX_VPP -DUSE_DRI3 -DUSE_EGL -DUSE_HEVC_DECODER -DUSE_VP8_DECODER -DUSE_WAYLAND -DUSE_WAYLAND_1_13 -DWITH_WAYLAND -DWITH_X11 -Dgstmfx_EXPORTS -I/opt/install/Custom_4159/include/mfx -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/gstreamer-1.0 -I/usr/include/orc-0.4 -I/usr/lib/x86_64-linux-gnu/gstreamer-1.0/include -I/usr/include/libdrm -I/opt/install/Custom_4159/include/libdrm -I. -I/opt/builder/source1/gstreamer-media-sdk -Igstreamer-media-sdk/gst/mfx -Igstreamer-media-sdk/gst-libs/mfx -Igstreamer-media-sdk/parsers -fPIC -std=gnu99 -Wall -fPIE -fstack-protector-strong  -fPIC -std=gnu99 -Wall -fPIE -fstack-protector-strong -D_FORTIFY_SOURCE=2 -O2 -fPIC -MD -MT CMakeFiles/gstmfx.dir/gst-libs/mfx/gstmfxdecoder.c.o -MF CMakeFiles/gstmfx.dir/gst-libs/mfx/gstmfxdecoder.c.o.d -o CMakeFiles/gstmfx.dir/gst-libs/mfx/gstmfxdecoder.c.o   -c gstreamer-media-sdk/gst-libs/mfx/gstmfxdecoder.c
  gstreamer-media-sdk/gst-libs/mfx/gstmfxdecoder.c:24:10: fatal error: gst/codecparsers/gsth264parser.h: No such file or directory
  #include <gst/codecparsers/gsth264parser.h>
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.

If dependency is optional, code shouldn't try to use it when it's missing (and if dependency is required, configuration phase should fail).

On Ubuntu 18.04, cgstreamer-codecparsers-1.0 is part of libgstreamer-plugins-bad1.0-dev package which pulls in huge number of deps (OpenCV, OpenCL, MySQL client...), so I'd rather do builds without needing to install half the world first.

[felixf4xu]

In my case, installation of libgstreamer-plugins-bad1.0-dev will fail, but it seems that it partially succeeds as well so that I can include the header file afterwards.

[cmake] -- Checking for modules 'gstreamer-1.0;gstreamer-app-1.0;gstreamer-video-1.0;gstreamer-codecparsers-1.0'
[cmake] --   Found gstreamer-1.0, version 1.14.5
[cmake] --   Found gstreamer-app-1.0, version 1.14.5
[cmake] --   Found gstreamer-video-1.0, version 1.14.5
[cmake] --   Found gstreamer-codecparsers-1.0, version 1.14.5