Recognize printf format string in OS::DebugMessage.

diff --git a/os.hpp b/os.hpp
index 0716784..4376c97 100644 (file)
--- a/os.hpp
+++ b/os.hpp
@@ -59,7 +59,11 @@ void ReleaseMutex(void);
 bool GetProcessName(char *str, size_t size);
 bool GetCurrentDir(char *str, size_t size);
 
-void DebugMessage(const char *format, ...);
+void DebugMessage(const char *format, ...)
+#ifdef __GNUC__
+    __attribute__ ((format (printf, 1, 2)))
+#endif
+;
 
 #if defined _WIN32 || defined __CYGWIN__
   /* We always use .def files on windows for now */