Calling a generator function returns a generator object

src/objects-debug.cc

Index: src/objects-debug.cc
diff --git a/src/objects-debug.cc b/src/objects-debug.cc
index 44cab53cc7ae90696e7c34929084e0e6e1e318bd..bbafa12679cdea1927dedad691bc48079a3c5332 100644
--- a/src/objects-debug.cc
+++ b/src/objects-debug.cc
@@ -139,6 +139,9 @@ void HeapObject::HeapObjectVerify() {
     case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
       JSObject::cast(this)->JSObjectVerify();
       break;
+    case JS_GENERATOR_OBJECT_TYPE:
+      JSGeneratorObject::cast(this)->JSGeneratorObjectVerify();
+      break;
     case JS_MODULE_TYPE:
       JSModule::cast(this)->JSModuleVerify();
       break;
@@ -404,6 +407,17 @@ void FixedDoubleArray::FixedDoubleArrayVerify() {
 }
 
 
+void JSGeneratorObject::JSGeneratorObjectVerify() {
+  // In an expression like "new g()", there can be a point where a generator
+  // object is allocated but its fields are all undefined, as it hasn't yet been
+  // initialized by the generator.  Hence these weak checks.
+  VerifyObjectField(kFunctionOffset);
+  VerifyObjectField(kContextOffset);
+  VerifyObjectField(kOperandStackOffset);
+  VerifyObjectField(kContinuationOffset);
+}
+
+
 void JSModule::JSModuleVerify() {
   VerifyObjectField(kContextOffset);
   VerifyObjectField(kScopeInfoOffset);