diff --git a/js/public/Utility.h b/js/public/Utility.h
index 29f3d520ce6..fec61699812 100644
--- a/js/public/Utility.h
+++ b/js/public/Utility.h
@@ -74,7 +74,7 @@ JS_BEGIN_EXTERN_C
 #define JS_FREE_PATTERN 0xDA
 
 #define JS_ASSERT(expr)           MOZ_ASSERT(expr)
-#define JS_ASSERT_IF(cond, expr)  MOZ_ASSERT_IF((cond), (expr))
+#define JS_ASSERT_IF(cond, expr)  MOZ_ASSERT_IF(cond, expr)
 #define JS_NOT_REACHED(reason)    MOZ_NOT_REACHED(reason)
 #define JS_ALWAYS_TRUE(expr)      MOZ_ALWAYS_TRUE(expr)
 #define JS_ALWAYS_FALSE(expr)     MOZ_ALWAYS_FALSE(expr)