Leads to segfault for Qt6 applications

[probonopd]

Preloading this leads to Qt5 being loaded in addition to Qt6, which leads to

% qtcreator
zsh: segmentation fault  qtcreator

We need to find a way to change QKeySequence::toString() without using LD_PRELOAD. Is the only way to recompile (parts of) Qt?

[jsm222]

Not tested at all but perhaps a full implementation like here helloSystem/hello#46 (comment) that not depend on existing binary lib symbol could sort out the Qt5/6 conflict..

[jsm222]

perhaps this change is the course https://codereview.qt-project.org/c/qt/qtbase/+/281289/42 I am looking into it..

[probonopd]

GammaRay is inserting something into running applications; before it does that, it seems to check for the Qt version, among other things ("probe ABI"):
https://github.com/KDAB/GammaRay/wiki/Troubleshooting

Not sure, but maybe we can learn something from there. It also seems to use LD_PRELOAD:
https://github.com/KDAB/GammaRay/blob/master/launcher/core/injector/preloadinjector.cpp

[jsm222]

The thing is that qt5 and qt6 shares the symbol we want to override so either if the preloaded so is compiled for qt5 it works with qt5, and the same for qt6 but not at the same time . in other words because the symbol we are overriding is the same in both qt versions we cannot preload two versions.