Investigating build system errors

[SilverCode]

When encountering build system errors like the following when running ./configure

ERROR: The OpenGL functionality tests failed!
You might need to modify the include and library search paths by editing QMAKE_INCDIR_OPENGL[_ES2],
QMAKE_LIBDIR_OPENGL[_ES2] and QMAKE_LIBS_OPENGL[_ES2] in the mkspec for your platform.

Looking in the config.log I see the following

loaded result for library config.qtbase_gui.libraries.opengl
Trying source 0 (type pkgConfig) of library opengl ...
+ /usr/bin/pkg-config --exists --silence-errors gl
pkg-config did not find package.
  => source produced no result.
Trying source 1 (type makeSpec) of library opengl ...
None of [libGL.so libGL.a] found in [] and global paths.
  => source produced no result.
test config.qtbase_gui.libraries.opengl FAILED

If I run the pkg-config check manually as above, the return code is 0, and getting the include and libs folders works

$ /usr/bin/pkg-config --exists --silence-errors gl
$ echo $?
0
$ pkg-config --libs --cflags gl
-I/usr/include/libdrm -lGL

So I'm not sure why the configure scripts are failing. I have this problem with other libraries like GStreamer 1.0 as well.

Where would I look to find the scripts which are testing the result of this output so I can try see why they are failing when the pkg-config command itself is succeeding?

This is on an Ubuntu 16.04 machine and I'm trying to compile Qt 5.13.0 from git with the command line:

~/qt5-build$ ../qt5/configure -opensource -nomake tests -nomake examples -prefix /opt/qt5/5.13.0 -webengine-proprietary-codecs -confirm-license

[SGaist]

Hi and welcome to devnet,

Are you targeting your desktop machine ?
Did you install all the build dependencies ? For example GStreamer development packages ?