Parser: fix confusion when there are multiple errors to report.

src/parser.cc

 // Copyright 2012 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 434 matching lines @@
   return identifier.is_identical_to(
              parser_->isolate()->factory()->eval_string()) ||
          identifier.is_identical_to(
              parser_->isolate()->factory()->arguments_string());
 }
 
 
 void ParserTraits::ReportMessageAt(Scanner::Location source_location,
                                    const char* message,
                                    Vector<const char*> args) {
+  if (parser_->stack_overflow()) {
+    // Suppress the error message (syntax error or such) in the presence of a
+    // stack overflow. The isolate allows only one pending exception at at time
+    // and we want to report the stack overflow later.
+    return;
+  }
   MessageLocation location(parser_->script_,
                            source_location.beg_pos,
                            source_location.end_pos);
   Factory* factory = parser_->isolate()->factory();
   Handle<FixedArray> elements = factory->NewFixedArray(args.length());
   for (int i = 0; i < args.length(); i++) {
     Handle<String> arg_string = factory->NewStringFromUtf8(CStrVector(args[i]));
     elements->set(i, *arg_string);
   }
   Handle<JSArray> array = factory->NewJSArrayWithElements(elements);
   Handle<Object> result = factory->NewSyntaxError(message, array);
   parser_->isolate()->Throw(*result, &location);
 }
 
 
 void ParserTraits::ReportMessage(const char* message,
                                  Vector<Handle<String> > args) {
   Scanner::Location source_location = parser_->scanner()->location();
   ReportMessageAt(source_location, message, args);
 }
 
 
 void ParserTraits::ReportMessageAt(Scanner::Location source_location,
                                    const char* message,
                                    Vector<Handle<String> > args) {
+  if (parser_->stack_overflow()) {
+    // Suppress the error message (syntax error or such) in the presence of a
+    // stack overflow. The isolate allows only one pending exception at at time
+    // and we want to report the stack overflow later.
+    return;
+  }
   MessageLocation location(parser_->script_,
                            source_location.beg_pos,
                            source_location.end_pos);
   Factory* factory = parser_->isolate()->factory();
   Handle<FixedArray> elements = factory->NewFixedArray(args.length());
   for (int i = 0; i < args.length(); i++) {
     elements->set(i, *args[i]);
   }
   Handle<JSArray> array = factory->NewJSArrayWithElements(elements);
   Handle<Object> result = factory->NewSyntaxError(message, array);
@@ skipping 4688 matching lines @@
       ASSERT(info()->isolate()->has_pending_exception());
     } else {
       result = ParseProgram();
     }
   }
   info()->SetFunction(result);
   return (result != NULL);
 }
 
 } }  // namespace v8::internal