Qt-contributors-summit-2014-QtCS2014 QtLoggingProfiling
Additional severity/type levels
There should be another level, e.g. QtInfoMsg, between QtDebugMsg and QtWarningMsg. Adding another enum will break sources, but that’s intentional.
QT_FATAL_WARNINGS
The “hammer” QT_FATAL_WARNINGS somewhat goes against the idea of categorized logging. It should be possible to make warnings fatal per category, to be able to e.g. make only Qt warnings fatal.
Another possiblity would be to not use QtWarningMsg in Qt, but QtSystemMsg, or even a new QtApiMisuseMsg …
Debugging/Inspector Protocol
GammaRay uses a network port too to inspect applications, like the QtQml debugger infrastructure does. There seems to be room for unification here … GamaRay though “injects” the networking part by LD_PRELOAD though (on all platforms), while QtQuick uses a command line argument (—qmljsdebugger) and Qt plugin.
In general we want to move away from Qt specific command line arguments, so adapting the LD_PRELOAD approach might be better … it also resolves some security issues. But things like attaching later to a running application is more error prone.