MantisBT - CMake
In the case of Phonon backends, it was impossible to load a backend (== a Qt plugin) compiled with MinGW without QT_DEBUG/QT_NO_DEBUG being defined.
This issue was detected only with MinGW, it worked fine with MSVC and Linux/GCC. Once the flags QT_DEBUG/QT_NO_DEBUG were added, the problem was solved.
This typically a kind of issue very difficult to solve, who thinks about a define not there when it works using other compilers/OS?
For the full story about how the problem was detected: http://groups.google.com/group/phonon-vlc-mplayer/browse_thread/thread/334efdff70fab22f [^]
How can other people not get into QT_DEBUG/QT_NO_DEBUG issue:
- QT_DEBUG/QT_NO_DEBUG are defined inside UseQt4.cmake
- a lot of libraries/apps only use FindQt4.cmake without using UseQt4.cmake
The solution I propose is to move QT_DEBUG/QT_NO_DEBUG definitions to FindQt4.cmake in order to prevent this.
Patch attached
FindQt4_QT_DEBUG.diff (1,834) 2008-05-29 14:14https://public.kitware.com/Bug/file/1510/FindQt4_QT_DEBUG.diff