diff --git a/src/share/vm/memory/metachunk.hpp b/src/share/vm/memory/metachunk.hpp
index 5ea8e235de67e76367ed57c5343a6a6ab360e53a..3bd4d15bca8d56945433d5db09f72f30d174ac4d 100644
--- a/src/share/vm/memory/metachunk.hpp
+++ b/src/share/vm/memory/metachunk.hpp
@@ -139,11 +139,12 @@ class Metachunk : public Metabase<Metachunk> {
   size_t free_word_size() const;
 
 #ifdef ASSERT
-  void mangle();
   bool is_tagged_free() { return _is_tagged_free; }
   void set_is_tagged_free(bool v) { _is_tagged_free = v; }
 #endif
 
+  NOT_PRODUCT(void mangle();)
+
   void print_on(outputStream* st) const;
   void verify();
 };