Fix issue 380.

src/rewriter.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 265 matching lines @@
 
 
 void AstOptimizer::VisitAssignment(Assignment* node) {
   ScopedFuncNameInferrer scoped_fni(&func_name_inferrer_);
   switch (node->op()) {
     case Token::INIT_VAR:
     case Token::INIT_CONST:
     case Token::ASSIGN:
       // No type can be infered from the general assignment.
 
-      scoped_fni.Enter();
+      // Don't infer if it is "a = function(){...}();"-like expression.
+      if (node->value()->AsCall() == NULL) {
+        scoped_fni.Enter();
+      }
       break;
     case Token::ASSIGN_BIT_OR:
     case Token::ASSIGN_BIT_XOR:
     case Token::ASSIGN_BIT_AND:
     case Token::ASSIGN_SHL:
     case Token::ASSIGN_SAR:
     case Token::ASSIGN_SHR:
       node->type()->SetAsLikelySmiIfUnknown();
       node->target()->type()->SetAsLikelySmiIfUnknown();
       node->value()->type()->SetAsLikelySmiIfUnknown();
@@ skipping 533 matching lines @@
     optimizer.Optimize(body);
     if (optimizer.HasStackOverflow()) {
       return false;
     }
   }
   return true;
 }
 
 
 } }  // namespace v8::internal