diff --git a/src/pike_memory.c b/src/pike_memory.c
index 18fda25edaac5205af38b3fc1eb7f6ad071207b6..e050786cb17dd45674744a08a936ed2e001f7964 100644
--- a/src/pike_memory.c
+++ b/src/pike_memory.c
@@ -787,7 +787,7 @@ void dump_memhdr_locations(struct memhdr *from,
   }
 }
 
-void cleanup_memhdrs()
+void cleanup_memhdrs(void)
 {
   unsigned long h;
   mt_lock(&debug_malloc_mutex);