tinyexr: Fixed OSX warning.

3rdparty/tinyexr/tinyexr.h

@@ -4377,7 +4377,7 @@ static FILE *mz_freopen(const char *pPath, const char *pMode, FILE *pStream) {
 #define MZ_FFLUSH fflush
 #define MZ_FREOPEN(f, m, s) freopen(f, m, s)
 #define MZ_DELETE_FILE remove
-#elif defined(__GNUC__) && _LARGEFILE64_SOURCE
+#elif defined(__GNUC__) && defined(_LARGEFILE64_SOURCE) && _LARGEFILE64_SOURCE
 #ifndef MINIZ_NO_TIME
 #include <utime.h>
 #endif