This file is part of MXE. See index.html for further information. This patch was taken from: https://sourceforge.net/p/mingw-w64/code/6479/ --- a/mingw-w64-headers/crt/math.h +++ b/mingw-w64-headers/crt/math.h @@ -36,7 +36,7 @@ #endif #endif -#ifndef __STRICT_ANSI__ +#if !defined(__STRICT_ANSI__) || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE) #define M_E 2.7182818284590452354 #define M_LOG2E 1.4426950408889634074 #define M_LOG10E 0.43429448190325182765