1 files changed, 6 insertions, 0 deletions
diff --git a/js/src/frontend/Parser.cpp b/js/src/frontend/Parser.cpp
index 5cb47f2425..cd586ad2a7 100644
--- a/js/src/frontend/Parser.cpp
+++ b/js/src/frontend/Parser.cpp
@@ -10949,6 +10949,12 @@ GeneralParser<ParseHandler, Unit>::memberPropertyAccess(
   if (handler_.isArgumentsName(lhs) && handler_.isLengthName(name)) {
     MOZ_ASSERT(pc_->numberOfArgumentsNames > 0);
     pc_->numberOfArgumentsNames--;
+    // Currently when resuming Generators don't get their argument length set
+    // in the interpreter frame (see InterpreterStack::resumeGeneratorCallFrame,
+    // and its call to initCallFrame).
+    if (pc_->isGeneratorOrAsync()) {
+      pc_->sc()->setIneligibleForArgumentsLength();
+    }
     return handler_.newArgumentsLength(lhs, name);
   }