Fix bug
Define a InterlockedAddNoFence64() function using gcc's atomics on
mingw(32|64)
(https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html)
#ifdef NNG_PLATFORM_WINDOWS
+//mingw does not define InterlockedAddNoFence64, use the mingw equivelent
+#ifdef __MINGW32__ || __MINGW64__
+#define InterlockedAddNoFence64(a,b) __atomic_add_fetch(a,b,__ATOMIC_RELAXED)
+#endif
+
#include <stdlib.h>
void *
