Building Qt 5 on Linux, for Windows - qt

Question

I wanted to migrate my Qt 4 app to use Qt 5 instead. These instructions failed, due to some differences with how MXE builds Qt 5, including the fact that it uses modularised Qt tarballs, instead of one large tarball.

Answer 1

Here are the full instructions:
Get it:
git clone https://github.com/mxe/mxe.git
Install build dependencies
Build Qt 5 for Windows:
cd mxe && make qtbase
This will first build its dependencies and the cross-build tools;
It should take less than an hour on a fast machine with decent internet access.
Due to the new modular nature of Qt 5, various major Qt components are now in different tarballs. The one selected above, qtbase, should give you enough functionality to run ordinary GUI apps, which is all I needed for my own (smallish) app.
If you want to build all of Qt 5 instead, you'll need to run make qt5 (instead of make qtbase). Note that it will take a lot longer to complete, so be sure that you need the extra functionality.
Get to the directory of your app, and run the Qt Makefile generator tool:
<mxe root>/usr/bin/i686-w64-mingw32.static-qmake-qt5
Build your project:
make
You should find the binary in the ./release directory:
wine release/foo.exe
Some notes:
This was tested on my 64-bit Debian 8, and on Windows of course.
The output is a 32-bit static executable, which will work well on 64-bit Windows.
If you want a 64-bit executable, build Qt with:
make MXE_TARGETS=x86_64-w64-mingw32.static qtbase
The default MXE_TARGETS value is i686-w64-mingw32.static.

Answer 2

The git checkout command is not correct. You now have to get their stable branch or it will fail building.
git clone https://github.com/mxe/mxe.git
should be...
git clone -b stable https://github.com/mxe/mxe.git
That alone fixed all my issues with qtbase building but leaving no qt folder when done. Then qt5 target would fail with obscure errors. Deleted folder, checked out stable and it worked flawlessly.

Answer 3

For those who directly want a GCC10 64bit compiled Qt5 (for filesystem lib for example),
Here are the full instructions:
Get it:
git clone https://github.com/mxe/mxe.git
Install build dependencies
Build Qt 5 for Windows with gcc10 64bits plugin activated :
cd mxe && make MXE_TARGETS=x86_64-w64-mingw32.shared MXE_PLUGIN_DIRS=plugins/gcc10 qt5
After 2-3 hours of build you can build your app (in your .pro directory) :
<mxe root>/usr/x86_64-w64-mingw32.shared/qt5/bin/qmake
Export path of compiler & build your project:
export PATH=<mxe root>/usr/bin:$PATH
make
You should find the binary in the ./release directory & start it with wine (or wine64) :
wine foo.exe
I don't really know why, but I needed to add the MXE compiler directory to the wine path because it's couldn't find the DLLs :
WINEPATH="<mxe root>/usr/x86_64-w64-mingw32.shared/bin/" wine64 foo.exe

Answer 4

If you try to do this, for me work fine!
su
mv mxe /opt/mxe
cd /opt/mxe && make