Meson build fail: Broken meson.build MediaSDK detection

[eero-t]

Setup:

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

Problem:

• With the included meson.build file, Meson doesn't find MediaSDK (whereas CMake finds it fine after CMake build fail: hard-coded to use static version of libmfx, although MediaSDK provides only shared one #146 fix)

This is because:

• find_library() adds weird/non-existing extra "lin_x64" path to MFX_HOME path
• Although MFX_HOME is given, compiler doesn't find mfx include files (meson.build doesn't add missing "/mfx/" after MFX_HOME)

Just removing the MFX_HOME weirdness and using standard pkg-config stuff instead makes things work:

--- a/meson.build
+++ b/meson.build
@@ -25,19 +25,15 @@ configure_file (input: 'version.h.in',
 
 mfx_sources = []
 mfx_c_args = []
-mfx_deps = []
 
 mfx_c_args += ['-std=gnu99', '-fPIE', '-fPIC']
 
 # Check the Media SDK
-mfx_home = get_option ('MFX_HOME')
+mfx_deps = [dependency('mfx')]
 
-mfx_inc = include_directories(['.', 'gst/mfx', 'gst-libs/mfx', 'parsers', '@0@/include'.format(mfx_home)])
+mfx_inc = include_directories(['.', 'gst/mfx', 'gst-libs/mfx', 'parsers'])
 
 compiler = meson.get_compiler('c')
-libmfx = compiler.find_library('mfx', dirs: '@0@/lib/lin_x64/'.format(mfx_home))
-mfx_deps += [libmfx]
-
 libstdcc = compiler.find_library('stdc++')
 mfx_deps += [libstdcc]
 

[eero-t]

One reason why use of something like MFX_HOME is bad, is that install target for your dependencies isn't necessarily a static thing.

Every one of our builds is done to a different directory (to retain build artifacts at the build server), i.e. MFX_HOME value would need to be re-generated every build. With pkg-config, everything works automatically, as pkg-config is something already supported by (Linux) build tools, and MediaSDK.