GCC for both x64 & x86 Windows! - MinGW-w64

Mingw-w64 is an advancement of the original mingw.org project, created to support the GCC compiler on Windows systems. It has forked it in 2007 in order to provide support for 64 bits and new APIs. It has since then gained widespread use and distribution. The development and community are very active and welcoming with new contributors every month and simple installers. Headers, Libraries and Runt

[qnighy]

MinGWのフォーク．大変良い

[AmaiSaeta]

"Mingw-w64 delivers runtime, headers and libs for developing both 64 bit (x64) and 32 bit (x86) windows applications using GCC and other free software compilers." | MinGW本家に欠けてる Windows SDK のヘッダが在ったり。