Fix background compilation disassembly: allocate string in old space instead of new space.

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 13722 matching lines @@
     return zone->PrintToString("Code entry:%" Px, EntryPoint());
   }
 }
 
 
 RawString* Code::Name() const {
   const Object& obj = Object::Handle(owner());
   if (obj.IsNull()) {
     // Regular stub.
     Thread* thread = Thread::Current();
-    Zone* zone = thread->zone();
     const char* name = StubCode::NameOfStub(EntryPoint());
     ASSERT(name != NULL);
-    const String& stub_name = String::Handle(zone, String::New(name));
+    const String& stub_name = String::Handle(Symbols::New(thread, name));
     return Symbols::FromConcat(thread, Symbols::StubPrefix(), stub_name);

[siva, 2016/04/13 20:29:48]

Why not do:

char* stub_name = OS::Screate(zone, "%s%s", Symbols::StubPrefix().ToCString(),
name);
return Symbols::New(thread, stub_name, strlen(stub_name));

[srdjan, 2016/04/13 20:38:16]

Done.

   } else if (obj.IsClass()) {
     // Allocation stub.
     Thread* thread = Thread::Current();
     Zone* zone = thread->zone();
     const Class& cls = Class::Cast(obj);
     String& cls_name = String::Handle(zone, cls.ScrubbedName());
     ASSERT(!cls_name.IsNull());
     return Symbols::FromConcat(thread, Symbols::AllocationStubFor(), cls_name);
   } else {
     ASSERT(obj.IsFunction());
@@ skipping 8264 matching lines @@
   return UserTag::null();
 }
 
 
 const char* UserTag::ToCString() const {
   const String& tag_label = String::Handle(label());
   return tag_label.ToCString();
 }
 
 }  // namespace dart