很久没有pacman我的msys2了，今天当我升级MSYS2 到2024年11月时，静态编译的UCRT64 和MingW64 版本的Qt6 都不工作了， 此外 Qt5 的 windeployqt也有依赖问题。解决：

1. qmake 静态编译附加库和 --no-merge 选项.

1.1 报错信息:

C:/msys64/ucrt64/bin/../lib/gcc/x86_64-w64-mingw32/14.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: C:/msys64/ucrt64/bin/../lib/gcc/x86_64-w64-mingw32/14.2.0/../../../../lib\libharfbuzz.a(hb-graphite2.cc.obj):(.text+0x18c): undefined reference to `gr_make_face_with_ops'
//...a lot

1.2 原因和解决

目前，尽管Qt6是静态编译的，但是很多依赖库不是静态的. QMake需要指定额外的依赖. 更进一步，因为库之间依赖的复杂性，需要禁用g++ 对库的重名合并功能(merge). 具体做法是加入这个代码到pro文件里去:

#Qt6 Widgets static link in MSYS2 need extra dependencies.
contains(QT, widgets){
MSYSTEM_PREFIX=$$(MSYSTEM_PREFIX)
greaterThan(MSYSTEM_PREFIX,' '){
contains(CONFIG, static) {message ("Perform Qt6 Static library with MSYS2 patch.")CONFIG += no_lflags_mergeLIBS += -ltiff  -lmng.dll -ljpeg -ljbig -ldeflate  -lzstd -llerc -llzma  -lgraphite2 -lbz2 -lusp10 -lRpcrt4 -lsharpyuv -lOleAut32
}
}
}

2.CMake 找不到 libuiautomationcore.a 的解决

要修改4个文件:

C:\msys64\mingw64\qt6-static\lib\cmake\Qt6Gui\Qt6QWindowsIntegrationPluginTargets-release.cmake
C:\msys64\mingw64\qt6-static\lib\cmake\Qt6Gui\Qt6QWindowsDirect2DIntegrationPluginTargets-release.cmake
C:\msys64\mingw64\qt6-static\lib\cmake\Qt6Gui\Qt6QWindowsIntegrationPluginTargets-release.cmake
C:\msys64\mingw64\qt6-static\lib\cmake\Qt6Gui\Qt6QWindowsDirect2DIntegrationPluginTargets-release.cmake

2.1 报错信息和解决

报错:

 "C:\msys64\ucrt64\bin\cmake.exe" --build B:/codes/helloWorld/build/Desktop_Qt_6_8_0_static_MinGW_w64_UCRT64_MSYS2-Release --target allninja: error: '/ucrt64/lib/libuiautomationcore.a', needed by 'helloWorld.exe', missing and no known rule to make it

解决：把四个文件里 libuiautomationcore.a 的路径去掉，只留文件名。

raw:  INTERFACE_LINK_LIBRARIES "...;/ucrt64/lib/libuiautomationcore.a;\$<LINK_ONLY:uuid>"

fix:

  INTERFACE_LINK_LIBRARIES "...;libuiautomationcore.a;\$<LINK_ONLY:uuid>"

2.2 原因分析:

尽管 msys2 支持类似Linux的虚拟路径，.但是cmake是从子进程的 cmd.exe 启动的，这个环境不懂 /ucrt64 是个啥。既然 msys2 已经根据当前环境配置了 lib 搜索路径，不如就直接删掉具体的绝对路径，让编译器自己找。

3. windepolyqt 对 GLES 库的依赖

这个问题发生在 qt5.15 身上. Windeployqt 需要安装 mingw-w64-ucrt-x86_64-angleproject 和 mingw64/mingw-w64-x86_64-angleproject才能运行完毕，否则会中途退出：

$ windeployqt /c/Test/helloWorld.exe
C:\Test\helloWorld.exe 64 bit, release executable
Adding Qt5Svg for qsvgicon.dll
Skipping plugin qtvirtualkeyboardplugin.dll due to disabled dependencies (Qt5Qml Qt5Quick).
Skipping plugin qtvirtualkeyboard_hangul.dll due to disabled dependencies (Qt5Qml Qt5Quick).
Skipping plugin qtvirtualkeyboard_openwnn.dll due to disabled dependencies (Qt5Qml Qt5Quick).
Skipping plugin qtvirtualkeyboard_pinyin.dll due to disabled dependencies (Qt5Qml Qt5Quick).
Skipping plugin qtvirtualkeyboard_tcime.dll due to disabled dependencies (Qt5Qml Qt5Quick).
Skipping plugin qtvirtualkeyboard_thai.dll due to disabled dependencies (Qt5Qml Qt5Quick).
Direct dependencies: Qt5Core Qt5Widgets
All dependencies   : Qt5Core Qt5Gui Qt5Widgets
To be deployed     : Qt5Core Qt5Gui Qt5Svg Qt5Widgets
Updating Qt5Core.dll.
Updating Qt5Gui.dll.
Updating Qt5Svg.dll.
Updating Qt5Widgets.dll.
C:\msys64\ucrt64\bin\libGLESv2.dll does not exist.

直接安装这两个库即可。