Temporary instrumentation to help understand lock errors on mac debug bots.

base/synchronization/lock_impl.h

Index: base/synchronization/lock_impl.h
===================================================================
--- base/synchronization/lock_impl.h	(revision 107048)
+++ base/synchronization/lock_impl.h	(working copy)
@@ -53,6 +53,19 @@
 #endif
 
  private:
+#if defined(OS_MAC) && !defined(NDEBUG)

[Mark Mentovai, 2011/10/28 19:58:26]

This won’t ever work. It’s OS_MACOSX.

You can add another #define inside this #ifdef so that you don’t need to keep
checking the same condition over and over again in the .cc file.

[eroman, 2011/10/28 20:00:53]

Thanks Mark!

I'll do that, and ping back once I have actually tested this :)  I just wanted
to get feedback early.

+  // Some instrumentation to help track down http://crbug.com/102161. Used to
+  // assert in debug builds when trying to use a freed lock.
+  enum LivenessToken {
+    LT_ALIVE = 0xCa11ab1e,
+    LT_DELETED = 0xDecea5ed,
+  };
+
+  void CheckIsAlive();
+
+  uint32 liveness_token_;
+#endif
+
   OSLockType os_lock_;
 
   DISALLOW_COPY_AND_ASSIGN(LockImpl);