--- a/js/src/frontend/ParseNode.cpp
+++ b/js/src/frontend/ParseNode.cpp
@@ -554,16 +554,17 @@ ParseNodeAllocator::freeTree(ParseNode* 
 void*
 ParseNodeAllocator::allocNode()
 {
     if (ParseNode* pn = freelist) {
         freelist = pn->pn_next;
         return pn;
     }
 
+    LifoAlloc::AutoFallibleScope fallibleAllocator(&alloc);
     void* p = alloc.alloc(sizeof (ParseNode));
     if (!p)
         ReportOutOfMemory(cx);
     return p;
 }
 
 ParseNode*
 ParseNode::appendOrCreateList(ParseNodeKind kind, JSOp op, ParseNode* left, ParseNode* right,