diff --git a/src/ast.cc b/src/ast.cc
index bf16b9c076..53d27999ea 100644
--- a/src/ast.cc
+++ b/src/ast.cc
@@ -1117,9 +1117,11 @@ void AstConstructionVisitor::VisitCallRuntime(CallRuntime* node) {
     // optimize them.
     add_flag(kDontInline);
   } else if (node->function()->intrinsic_type == Runtime::INLINE &&
-             node->raw_name()->IsOneByteEqualTo("_Arguments")) {
-    // Don't inline the %_Arguments because it's implementation will not work.
-    // There is no stack frame to get them from.
+             (node->raw_name()->IsOneByteEqualTo("_ArgumentsLength") ||
+              node->raw_name()->IsOneByteEqualTo("_Arguments"))) {
+    // Don't inline the %_ArgumentsLength or %_Arguments because their
+    // implementation will not work.  There is no stack frame to get them
+    // from.
     add_flag(kDontInline);
   }
 }
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index d447bbc9f7..6ae1466d62 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -11310,17 +11310,13 @@ void HOptimizedGraphBuilder::GenerateIsConstructCall(CallRuntime* call) {
 
 // Support for arguments.length and arguments[?].
 void HOptimizedGraphBuilder::GenerateArgumentsLength(CallRuntime* call) {
+  // Our implementation of arguments (based on this stack frame or an
+  // adapter below it) does not work for inlined functions.  This runtime
+  // function is blacklisted by AstNode::IsInlineable.
+  ASSERT(function_state()->outer() == NULL);
   ASSERT(call->arguments()->length() == 0);
-  HInstruction* result = NULL;
-  if (function_state()->outer() == NULL) {
-    HInstruction* elements = Add<HArgumentsElements>(false);
-    result = New<HArgumentsLength>(elements);
-  } else {
-    // Number of arguments without receiver.
-    int argument_count = environment()->
-        arguments_environment()->parameter_count() - 1;
-    result = New<HConstant>(argument_count);
-  }
+  HInstruction* elements = Add<HArgumentsElements>(false);
+  HArgumentsLength* result = New<HArgumentsLength>(elements);
   return ast_context()->ReturnInstruction(result, call->id());
 }