Index: runtime/vm/dart_api_impl.cc |
diff --git a/runtime/vm/dart_api_impl.cc b/runtime/vm/dart_api_impl.cc |
index 4a7da5f0a50913e3165087cd3b162c9b3de072b0..6e668c84ffb555a4adbea9a2016dcf1beaba48fd 100644 |
--- a/runtime/vm/dart_api_impl.cc |
+++ b/runtime/vm/dart_api_impl.cc |
@@ -382,6 +382,7 @@ Dart_Handle Api::NewHandle(Isolate* isolate, RawObject* raw) { |
RawObject* Api::UnwrapHandle(Dart_Handle object) { |
#if defined(DEBUG) |
+ ASSERT(Thread::Current()->IsMutatorThread()); |
Isolate* isolate = Isolate::Current(); |
ASSERT(isolate != NULL); |
ApiState* state = isolate->api_state(); |