MSYS2

Use GCC on Windows

see also Installing GCC & MSYS2

msys32

• toolchain installation/update script

    inst-msys-i686.sh

• add to .bash_profile

    export MINGW_CHOST="i686-w64-mingw32"
    export MINGW_PREFIX="mingw32"
    PATH="${PATH}:/${MINGW_PREFIX}/bin"

msys64

• toolchain installation/update script

    inst-msys-x86_64.sh 

• add to .bash_profile

    export MINGW_CHOST="x86_64-w64-mingw32"
    export MINGW_PREFIX="mingw64"
    PATH="${PATH}:/${MINGW_PREFIX}/bin"