• Various CMake improvements:
• The toolchain files /usr/share/data/mingw/toolchain-mingw32.cmake and /usr/share/data/mingw/toolchain-mingw64.cmake don't have an uppercase character in their file name any more
• Add CMAKE_SYSTEM_PROCESSOR to the CMake toolchain files
• Removed Boost_COMPILER from the CMake toolchain files as it was unused and broken anyway
• Made the RPM macros mingw32_cmake, mingw32_cmake_kde4, mingw64_cmake and mingw64_cmake_kde4 more generic
• Removed the rpath references as mingw doesn't support rpath
• Allow verbose CMake output to be disabled by setting the environment variable MINGW_CMAKE_NO_VERBOSE (RHBZ #987644)
• When calling the mingw32-cmake and mingw64-cmake wrapper scripts don't use verbose CMake output by default
• When using the CMake wrappers, prevent CFLAGS and CXXFLAGS from being set unless they're already set in the current environment (RHBZ #1136069)
• Don't set LIB_INSTALL_DIR any more in the CMake macros as it breaks CPack and isn't needed by any of the Fedora MinGW packages (RHBZ #1152696)
• Accept empty MINGW{32,64}_{C,CPP,CXX}FLAGS environment variables
• Removed old _mingw32 macros which have been deprecated since Fedora 17

For more details see https://lists.fedoraproject.org/pipermail/mingw/2015-April/009020.html