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  • Dear all,

    I have the following issue : my projects is compiled with the QT_NO_DYNAMIC_CAST defined in the compiler command line option "-DQT_NO_DYNAMIC_CAST" as I can see in QtCreator compiler output. This causes the compilation to fail due to the use of dynamic_cast

    Here are details about the problem:

    • Qt is 4.8.1 compiled with MSVC2010 for x64 platform (64-bit)
    • I did not specify "-no-rtti" to configure, so I suppose the as-stated-in-documentation default "-rtti" was used
    • I checked in the mkspecs/win32-msvc2010 .conf file. Nothing related to RTTI or QT_NO_DYNAMIC_CAST

    And the questions:

    • Where is defined the QT_NO_DYNAMIC_CAST? Neither in the mkspec, nor in my .pro apparently. Also not in my QtCreator build settings. So I really do not know where to disable it...
    • Any other idea?
    • Do I have to recompile Qt?



  • Please post your mkspecs/qconfig.pri.

  • Hi Lukas

    Thanks for your interest in this issue.
    I have actually no qconfig.pri in mkspecs. I checked in the two builds I have installed as binaries with the SDK (MinGW and MSVC x86), they have mkspecs/qconfig.pri. But in the source package I have downloaded, "", there is no such file. And apparently, none was generated during the build, or it was cleaned by the nmake confclean.



  • Hi again,

    Seems that "nmake confclean" did remove the qconfig.pri, which should contain CONFIG += rtti
    To avoid recompiling everything, I took the qconfig.pri from the msvc2010 32bit binary, and it seems to work. I will make a full rebuild some day...

    Is there any clean way to strip the qt build so that it is as small as a distributed binary build?



  • <code>make install</code>

  • Hi,

    I will recheck, but I think that make install is not supported for windows builds


  • After some tests, make install does work in windows, but the -prefix option does not. So it installs in the source directory...

    However, I found the solution on another forum. configure.exe may be called from an empty directory using the full path to configure.exe. Then make, make install and make clean do a clean installation inside this previously empty directory. Works perfectly

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