diff --git a/js/src/jsdhash.c b/js/src/jsdhash.c
index 199c17d4d22f..295883b2fdfe 100644
--- a/js/src/jsdhash.c
+++ b/js/src/jsdhash.c
@@ -77,8 +77,8 @@
 #else
 
 #define ENTRY_STORE_EXTRA 0
-#define INCREMENT_RECURSION_LEVEL(table_) 1
-#define DECREMENT_RECURSION_LEVEL(table_) 0
+#define INCREMENT_RECURSION_LEVEL(table_)   ((void)1)
+#define DECREMENT_RECURSION_LEVEL(table_)   ((void)0)
 
 #endif /* defined(DEBUG) */
 
diff --git a/js/src/plify_jsdhash.sed b/js/src/plify_jsdhash.sed
index 9c742f407ae7..eff4901c5fe6 100644
--- a/js/src/plify_jsdhash.sed
+++ b/js/src/plify_jsdhash.sed
@@ -28,5 +28,6 @@ s/JS_PUBLIC_API(\([^()]*\))/\1/
 s/JS_DLL_CALLBACK/PR_CALLBACK/
 s/JS_STATIC_DLL_CALLBACK/PR_STATIC_CALLBACK/
 s/JS_NewDHashTable/PL_NewDHashTable/
+s/JS_ASSERT(0)/NS_NOTREACHED("0")/
 s/\( *\)JS_ASSERT(\(.*\));/\1NS_ASSERTION(\2,\n\1             "\2");/
 s/JS_/PR_/g
diff --git a/xpcom/glue/pldhash.c b/xpcom/glue/pldhash.c
index dda78660c5b5..ee715bd66d64 100644
--- a/xpcom/glue/pldhash.c
+++ b/xpcom/glue/pldhash.c
@@ -78,8 +78,8 @@
 #else
 
 #define ENTRY_STORE_EXTRA 0
-#define INCREMENT_RECURSION_LEVEL(table_) 1
-#define DECREMENT_RECURSION_LEVEL(table_) 0
+#define INCREMENT_RECURSION_LEVEL(table_)   ((void)1)
+#define DECREMENT_RECURSION_LEVEL(table_)   ((void)0)
 
 #endif /* defined(DEBUG) */
 
@@ -632,8 +632,7 @@ PL_DHashTableOperate(PLDHashTable *table, const void *key, PLDHashOperator op)
         break;
 
       default:
-        NS_ASSERTION(0,
-                     "0");
+        NS_NOTREACHED("0");
         entry = NULL;
     }