Store the callstack of the IPC sender of ViewMsg_New

content/renderer/render_frame_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/render_frame_impl.h"
 
 #include <map>
 #include <string>
 
 #include "base/auto_reset.h"
@@ skipping 657 matching lines @@
       geolocation_dispatcher_(NULL),
       push_messaging_dispatcher_(NULL),
       presentation_dispatcher_(NULL),
       screen_orientation_dispatcher_(NULL),
       manifest_manager_(NULL),
       accessibility_mode_(AccessibilityModeOff),
       renderer_accessibility_(NULL),
       weak_factory_(this) {
   std::pair<RoutingIDFrameMap::iterator, bool> result =
       g_routing_id_frame_map.Get().insert(std::make_pair(routing_id_, this));
-  CHECK(result.second) << "Inserting a duplicate item.";
+  if (!result.second) {
+    // TODO(lfg): Temporary. We're about to force a crash, so save the debug
+    // info on the stack so we can recover it from the crash dumps.
+    RenderFrameImpl* duplicate = result.first->second;
+    const std::vector<unsigned long>& debug_info = render_view->debug_info();
+    const std::vector<unsigned long>& duplicate_debug_info =
+        duplicate->render_view()->debug_info();
+    unsigned long duplicate_stack_debug_info[128];
+    unsigned long stack_debug_info[128];
+    const int size = debug_info.size() > 128 ? 128 : debug_info.size();
+    const int duplicate_size =
+        duplicate_debug_info.size() > 128 ? 128 : duplicate_debug_info.size();
+    memcpy(&stack_debug_info, &debug_info[0], size * sizeof(unsigned long));

[nasko, 2015/03/16 18:38:26]

memcpy from the memory of a stl container sounds scary to me. Why not just loop
and copy over the addresses, which will be simpler and since this will be
crashing, performance isn't really critical.

Also, why can't we just use debug::Alias() to force values to show up on the
stack? Have you tried that route?

+    memcpy(&duplicate_stack_debug_info, &duplicate_debug_info[0],
+           duplicate_size * sizeof(unsigned long));
+    CHECK(result.second) << "Inserting a duplicate item.";
+  }
 
   RenderThread::Get()->AddRoute(routing_id_, this);
 
   render_view_->RegisterRenderFrame(this);
 
   // Everything below subclasses RenderFrameObserver and is automatically
   // deleted when the RenderFrame gets deleted.
 #if defined(OS_ANDROID)
   new GinJavaBridgeDispatcher(this);
 #endif
@@ skipping 3826 matching lines @@
 
 #if defined(ENABLE_BROWSER_CDMS)
 RendererCdmManager* RenderFrameImpl::GetCdmManager() {
   if (!cdm_manager_)
     cdm_manager_ = new RendererCdmManager(this);
   return cdm_manager_;
 }
 #endif  // defined(ENABLE_BROWSER_CDMS)
 
 }  // namespace content