[ 37%] Built target IlmImf
[ 37%] Built target libprotobuf
C:/Qt/Qt5.14.2/Tools/mingw730_64/bin/../lib/gcc/x86_64-w64-mingw32/7.3.0/../../.
./../x86_64-w64-mingw32/bin/ld.exe: i386 architecture of input file `CMakeFiles\
opencv_core.dir/objects.a(vs_version.rc.obj)' is incompatible with i386:x86-64 o
utput
collect2.exe: error: ld returned 1 exit status
mingw32-make[2]: *** [modules\core\CMakeFiles\opencv_core.dir\build.make:1630: b
in/libopencv_core453d.dll] Error 1
mingw32-make[1]: *** [CMakeFiles\Makefile2:1749: modules/core/CMakeFiles/opencv_
core.dir/all] Error 2
mingw32-make: *** [Makefile:165: all] Error 2
解决方法：
Problem is somewhere here (added for 3.3.0 release). Like @mshabunin said take a look on CMAKE_RC_COMPILER variable.
Or try using OPENCV_VS_VERSIONINFO_SKIP=1 CMake option.
cmake里面手动添加：OPENCV_VS_VERSIONINFO_SKIP
cmake界面按钮： add Entry --->>> BOOL --->>> OPENCV_VS_VERSIONINFO_SKIP 打钩
