mingw-w64-qt5-base (5.7.0-8): CMake qt5_wrap_ui adds Qt5::uic to uic command line

[JayFoxRox]

I'm trying to compile github.com/citra-emu/citra with mingw.

I'm getting the following problem (mingw-w64-qt5-base 5.7.0-8 on both x64 and i686 using the mingw CMake wrappers):

[ 86%] Generating ui_main.h
cd /home/fox/Data/Projects/citra/build-x86_64-w64-mingw32/src/citra_qt && /usr/x86_64-w64-mingw32/lib/qt/bin/uic Qt5::uic -o /home/fox/Data/Projects/citra/build-x86_64-w64-mingw32/src/citra_qt/ui_main.h /home/fox/Data/Projects/citra/src/citra_qt/main.ui
File 'Qt5::uic' is not valid

A native Linux build (qt5-base 5.7.0-7 x64) does this:

[ 87%] Generating ui_main.h
cd /home/fox/Data/Projects/citra/build/src/citra_qt && /usr/bin/uic -o /home/fox/Data/Projects/citra/build/src/citra_qt/ui_main.h /home/fox/Data/Projects/citra/src/citra_qt/main.ui

It appears that CMake qt5_wrap_ui(UI_HDRS ${UIS}) (or some wrapper invoking uic) provided by the mingw qt5 is somehow broken?
Unfortunately the citra codebase is not AUTOUIC ready, so I did not try it with that yet.

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As this issue does not exist natively I'm assuming it's a bug in the package?
Is there anything else you can recommend I should try or is there a known workaround for this issue?

I've tried finding other people who are affected but found nothing yet.

[Martchus]

Yes, looks like a bug in the package or the mingw-w64/Windows version of Qt. Since I lately patched the CMake files in order to provide support to use static build with CMake I might have messed something.

The latest version (5.7.0-9, found in the repository on GitHub and my binary repo) might work better, but I wouldn't bet on it.

AUTOUIC would work in general. I use it in my own projects instead of qt5_wrap_ui so I didn't notice that this function is broken.

I'll look into this next week. Until then, you could just not apply the patch 0022-Allow-usage-of-static-version-with-CMake.patch (which is the mentioned patch for static build). Other patches also modify the CMake files (like 0020-Use-.dll.a-as-import-lib-extension.patch) and hance are also possible candidates.

You can also play with the installed CMake files. Maybe you find a fix. I can include those changes into the package then. Just in case you can provide a patch, patches are managed here.

[JayFoxRox]

I've tried to find the cause of this and I'm absolutely clueless what goes on.
Aside from a single change in /usr/i686-w64-mingw32/lib/cmake/Qt5Widgets/Qt5WidgetsConfigExtras.cmake (prefixing the path) the (Qt5Widgets) CMake files seem to be the same for linux, windows and mingw.

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I noticed the following behaviour in /usr/i686-w64-mingw32/lib/cmake/Qt5Widgets/Qt5WidgetsMacros.cmake . I'm not sure if that means anything though:

add_custom_command(OUTPUT ${outfile}
          COMMAND ${Qt5Widgets_UIC_EXECUTABLE}

Will expand ${Qt5Widgets_UIC_EXECUTABLE} to "/usr/i686-w64-mingw32/lib/qt/bin/uic Qt5::uic"

add_custom_command(OUTPUT ${outfile}
          COMMAND FOO ${Qt5Widgets_UIC_EXECUTABLE}

Will expand ${Qt5Widgets_UIC_EXECUTABLE} to "FOO Qt5::uic". This suggests that Qt5::uic is supposed to be replaced by the uic path, which doesn't happen, as it's merely prefixed for some strange reason?!

add_custom_command(OUTPUT ${outfile}
          COMMAND FOO ${Qt5Widgets_UIC_EXECUTABLE} BAR

Will expand ${Qt5Widgets_UIC_EXECUTABLE} to "FOO Qt5::uic BAR"

add_custom_command(OUTPUT ${outfile}
          COMMAND ${Qt5Widgets_UIC_EXECUTABLE} BAR

Will expand ${Qt5Widgets_UIC_EXECUTABLE} to "/usr/i686-w64-mingw32/lib/qt/bin/uic Qt5::uic BAR"

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As a temporary workaround I'll attempt to switch to AUTOUIC, maybe compile without 0022 and 0020

[Martchus]

Ok, then I guess my patches are not the source of the problem.

But this reminds me of a similar problem with the macros provided by Qt Linguist (part of qt5-tools): Martchus/qttools@1f1a8e6

As you can see I've already found a workaround for this. You might be able to apply the same workaround for uic.

[Martchus]

If this is correct, the following patch might fix the issue: Martchus/qtbase@7e20d46

[Martchus]

So, does this little change work for you? You don't need to rebuild the package to test, just modify installed file.

[JayFoxRox]

Oh I forgot to get back to this. I've implemented my own hack which was a lot more cruel:

set(Qt5Widgets_UIC_EXECUTABLE ${_qt5Widgets_install_prefix}/lib/qt/bin/uic)

( in /usr/{i686,x86_64}-w64-mingw32/lib/cmake/Qt5Widgets/Qt5WidgetsConfigExtras.cmake )
I only really needed this to test one PR in citra so I didn't try your solution either.

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However, being well aware how annoying it is to reproduce issues, I've also tried your hack (I wouldn't dare to call it a patch) now: It does also work.
Let's hope you find the real cause of the issue soon so these ugly kludges can be removed.

[Martchus]

Ok, then I close this. Maybe ask CMake devs.

Thanks for feedback and reproducing.