Hi,
I've downloaded and installed Qt5.5 precompiled with MinGw 4.92.
After that I tried to compile my old projects (created with Qt for VisualStudio).
This binary compiles - fails during linkage.
Qt Code:
  1. || [ 42%] Built target log4cpp
  2. || [ 45%] Built target tools_lib
  3. || [ 46%] Automatic moc for target PhoneticNumberSystem
  4. || [ 46%] Built target PhoneticNumberSystem_automoc
  5. || [ 47%] Linking CXX executable PhoneticNumberSystem.exe
  6. || CMakeFiles\PhoneticNumberSystem.dir/objects.a(CAppSettings.cpp.obj):CAppSettings.cpp:(.text+0xd7c): undefined reference to `_imp___ZN7QObjectC2EPS_'
  7. || CMakeFiles\PhoneticNumberSystem.dir/objects.a(CAppSettings.cpp.obj):CAppSettings.cpp:(.text+0xe72): undefined reference to `_imp___ZN7QObjectD2Ev'
  8. || CMakeFiles\PhoneticNumberSystem.dir/objects.a(CAppSettings.cpp.obj):CAppSettings.cpp:(.text+0xebc): undefined reference to `_imp___ZN7QObjectD2Ev'
  9. || CMakeFiles\PhoneticNumberSystem.dir/objects.a(CDataThread.cpp.obj):CDataThread.cpp:(.text+0x1d3): undefined reference to `_imp___ZN4QDirC1ERK7QString'
  10. || CMakeFiles\PhoneticNumberSystem.dir/objects.a(CDataThread.cpp.obj):CDataThread.cpp:(.text+0x1f8): undefined reference to `_imp___ZN4QDirD1Ev'
  11. || CMakeFiles\PhoneticNumberSystem.dir/objects.a(CDataThread.cpp.obj):CDataThread.cpp:(.text+0x35f): undefined reference to `_imp___ZN4QDirD1Ev'
  12. || CMakeFiles\PhoneticNumberSystem.dir/objects.a(CDataThread.cpp.obj):CDataThread.cpp:(.text+0x500): undefined reference to `_imp___ZN4QDir9separatorEv'
  13. || CMakeFiles\PhoneticNumberSystem.dir/objects.a(CDataThread.cpp.obj):CDataThread.cpp:(.text+0x7a6): undefined reference to `_imp___ZN4QDir9separatorEv'
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Here what CMakeLists.txt for main binary looks like http://pastebin.com/Bk5Jq0ZR
g++ (GCC) 4.8.1
In system environment I added variable QT_DIR=d:\Qt\Qt5.5.1\5.5\mingw492_32
and added it to PATH like => %QT_DIR%;%QT_DIR%\bin;%QT_DIR%\include;%QT_DIR%\li b

Obviously, linker can't find proper objects in proposed libraries. Now, should I rebuild entire Qt to fit G++ 4.8? Should I install more recent MinGw version with newer g++? Or some other CMake settings changes are needed?