Hello,

I have had some problems to compile vlc, clementine, avidemux, using qt5-5.7.0 (from AlienBob's kde5), in slackware64-current. There are error messages about "C++11 support".
For avidemux the problem can be solved by doing

export CXXFLAGS=-std=c++11

before "configure". This does not work with vlc and clementine. I had to remove qt5, compile vlc and clementine (using qt4) and reinstall qt5.

Would compilation with qt5 work with testing/gcc-6.2.0 instead of gcc-5.4.0 ? And if I replace gcc-5.4.0 with testing/gcc-6.2.0, will some older programs fail to compile ?

Toutatis, I use Slack 64-current with AlienBob's latest Plasma packages so I also have qt-5.7 installed. And I also ran into a number of problems when compiling several SlackBuilds which used qt or qt5. In these cases I edited the SLCKFLAGS to append the "-std=c++11" flag and usuall that solved the issue. IIRC clementine 1.31 only works with qt4. For VLC I would recommend grabbing AlienBob's latest package.

I've also been curious about whether qt4 and 5 can co-exist and if so, what the caveats are. However, I suppose that's for another thread..

@drew2x: they can and they do, usually without any problem. I have both versions installed.

I build QT 5.7 with GCC default(5.x) + ffmpeg 3.x + VLC 3(git)
success!