Fixed bug 3092 - Statically link sdl2 with /MT for msvc

Martin Gerhardy

According to https://msdn.microsoft.com/de-de/library/2kzt1wy3%28v=vs.120%29.aspx when one is using /MT for msvc compilations the libcmt.lib is already linked to the binary. This lib includes the symbol that is now guarded (see attached patch) by the #ifndef _MT.

src/stdlib/SDL_stdlib.c

@@ -275,8 +275,11 @@ int SDL_tolower(int x) { return ((x) >= 'A') && ((x) <= 'Z') ? ('a'+((x)-'A')) :
 
 #ifndef __FLTUSED__
 #define __FLTUSED__
+/* the multithreaded runtime already includes libcmt.lib - and this symbol is in there. */
+#ifndef _MT
 __declspec(selectany) int _fltused = 1;
 #endif
+#endif
 
 /* The optimizer on Visual Studio 2005 and later generates memcpy() calls */
 #if (_MSC_VER >= 1400) && defined(_WIN64) && !defined(_DEBUG)