let me remind you that qtractor is currently recommended for packaging as a qt4 only application;
building it as a qt5 one, although perfectly functional and operational, it will end as an utterly crippled audio/MIDI application on some rather important features, mostly on the LV2 plugin GUI support
that said, only the lv2_external_ui (unofficial) extension is then supported; there will be NO libSUIL wrapped amenities whatsoever, that meaning that most if not all native GTK+, X11 or even Qt4 plugin GUIs will be ditched out or completely forbidden--some will even crash on show.
this is all very distro dependant, if i may say, and very qt5 specific too :/
if both qt5 and qt4 are installed on your system and the default is qt5, then i'd suggest you to try
./configure --enable-qt5...or
./configure --disable-qt4...in either case, if qt5 is not the system selected default, then maybe you'll need something like this:
./configure --enable-qt5 --with-qt=/opt/Qt5.x.y/5.x.y/gcc ...let me remind you that qtractor is currently recommended for packaging as a qt4 only application;
building it as a qt5 one, although perfectly functional and operational, it will end as an utterly crippled audio/MIDI application on some rather important features, mostly on the LV2 plugin GUI support
that said, only the lv2_external_ui (unofficial) extension is then supported; there will be NO libSUIL wrapped amenities whatsoever, that meaning that most if not all native GTK+, X11 or even Qt4 plugin GUIs will be ditched out or completely forbidden--some will even crash on show.
hth.
cheers