diff --git a/Source/JavaScriptCore/runtime/JSCell.cpp b/Source/JavaScriptCore/runtime/JSCell.cpp
index e050a53..739247f 100644
--- a/Source/JavaScriptCore/runtime/JSCell.cpp
+++ b/Source/JavaScriptCore/runtime/JSCell.cpp
@@ -199,7 +199,7 @@
     ASSERT_NOT_REACHED();
 }
 
-bool JSCell::hasInstance(JSObject*, ExecState*, JSValue, JSValue)
+bool JSCell::customHasInstance(JSObject*, ExecState*, JSValue)
 {
     ASSERT_NOT_REACHED();
     return false;