diff --git a/include/asterisk/compat.h b/include/asterisk/compat.h
index 43da49bc0582ad272b6a49d6b5dde0d574841da6..4ba4c46d4ba68306e5917342a7ebcedd5c24fd79 100644
--- a/include/asterisk/compat.h
+++ b/include/asterisk/compat.h
@@ -74,7 +74,7 @@
 #endif
 
 #if !defined(HAVE_ASPRINTF) && !defined(__AST_DEBUG_MALLOC)
-int asprintf(char **str, const char *fmt, ...);
+int __attribute__ ((format (printf, 2, 3))) asprintf(char **str, const char *fmt, ...);
 #endif
 
 #ifndef HAVE_GETLOADAVG