__MINGW64_VERSION_MAJOR is defined only in _mingw.h, so it was never defined in wx/compiler.h, included before any other headers and we can't include _mingw.h for the same reason we must define wxCHECK_MINGW32_VERSION() in wx/msw/gccpriv.h: this has to be done after defining UNICODE/_UNICODE, but wx/compiler.h is included before this. git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@77533 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775