Qt5 Cmake module fails to find GL

[computerquip]

I don't even know what to say about this... but apparently, Qt5 modules fails to find GL because it defaults to the hardcoded path of (/usr/X11R6/lib64) regardless of architecture in use, probably one of the worst assumptions ever. Especially so since /usr/X11R6 hasn't been a good idea since ever and isn't even currently used on at least Ubuntu 14.04 (let alone any other sane distribution)

_qt5gui_find_extra_libs(OPENGL "GL" "/usr/X11R6/lib64" "")

Output describing issue here: https://gist.github.com/computerquip/586444750f06b865fba9

Changing it manually via cmake variable assignment works... but you can literally assign it anything and cmake is happy.

Anyways, these Cmake modules are actually parts of the Qt5 package in Ubuntu, rather than coming from cmake (like most other modules). Qt5 is not supported in upstream cmake as seen here: http://www.cmake.org/cmake/help/v3.2/manual/cmake-modules.7.html

I'm not sure what a good solution would be here. Maybe just change that specific variable to a more sane default? Unfortunately, it won't be easy since Debian/Ubuntu don't like to make things simple and use {/usr}/lib/x86_64-linux-blah-blah rather than just /usr/lib.

[computerquip]

For what it's worth, Ubuntu 14.04 packages Qt5 5.2.1 which seems to be very recent.

[computerquip]

Actually, I can't reproduce this anymore. I don't know what dependency or update that happened to know what was going on... apologies. I'll close this issue for now though since it doesn't appear to be an actual issue, albeit slightly unintuitive.