1 files changed, 12 insertions, 3 deletions
diff --git a/includes/rts/Messages.h b/includes/rts/Messages.h
index 6f59d1dc3e..d3dabde3a9 100644
--- a/includes/rts/Messages.h
+++ b/includes/rts/Messages.h
@@ -19,6 +19,15 @@
 
 #include <stdarg.h>
 
+#if defined(mingw32_HOST_OS)
+/* On Win64, if we say "printf" then gcc thinks we are going to use
+   MS format specifiers like %I64d rather than %llu */
+#define PRINTF gnu_printf
+#else
+/* However, on OS X, "gnu_printf" isn't recognised */
+#define PRINTF printf
+#endif
+
 /* -----------------------------------------------------------------------------
  * Message generation
  * -------------------------------------------------------------------------- */
@@ -48,7 +57,7 @@ void vbarf(const char *s, va_list ap)
  * errorBelch() invokes (*errorMsgFn)().
  */
 void errorBelch(const char *s, ...)
-   GNUC3_ATTRIBUTE(format (printf, 1, 2));
+   GNUC3_ATTRIBUTE(format (PRINTF, 1, 2));
 
 void verrorBelch(const char *s, va_list ap);
 
@@ -62,7 +71,7 @@ void verrorBelch(const char *s, va_list ap);
  * sysErrorBelch() invokes (*sysErrorMsgFn)().
  */
 void sysErrorBelch(const char *s, ...)
-   GNUC3_ATTRIBUTE(format (printf, 1, 2));
+   GNUC3_ATTRIBUTE(format (PRINTF, 1, 2));
 
 void vsysErrorBelch(const char *s, va_list ap);
 
@@ -74,7 +83,7 @@ void vsysErrorBelch(const char *s, va_list ap);
  * debugBelch() invokes (*debugMsgFn)().
  */
 void debugBelch(const char *s, ...)
-   GNUC3_ATTRIBUTE(format (printf, 1, 2));
+   GNUC3_ATTRIBUTE(format (PRINTF, 1, 2));
 
 void vdebugBelch(const char *s, va_list ap);