diff --git a/src/gmalloc.c b/src/gmalloc.c
index 598d802badc..77fb3197101 100644
--- a/src/gmalloc.c
+++ b/src/gmalloc.c
@@ -36,8 +36,9 @@ Cambridge, MA 02139, USA.
 #include <config.h>
 #endif
 
-#if defined __cplusplus || (defined (__STDC__) && __STDC__) || \
-  defined STDC_HEADERS || defined PROTOTYPES
+#if ((defined __cplusplus || (defined (__STDC__) && __STDC__) \
+      || defined STDC_HEADERS || defined PROTOTYPES) \
+     && ! defined (BROKEN_PROTOTYPES))
 #undef	PP
 #define	PP(args)	args
 #undef	__ptr_t