Added dynamic annotation files into base/.

Added annotations for atomic reference counting, LazyInstance and Singleton classes.

This changelist is a part of an effort of adding ThreadSanitizer support for Chromium.
See http://code.google.com/p/data-race-test/wiki/ThreadSanitizer

Patch by Timur Iskhodzhanov.

Review URL: http://codereview.chromium.org/147008


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@19353 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 9 insertions, 0 deletions

diff --git a/base/lazy_instance.h b/base/lazy_instance.h
index 1705b0f..d0cc109 100644
--- a/base/lazy_instance.h
+++ b/base/lazy_instance.h
@@ -37,6 +37,7 @@
 
 #include "base/atomicops.h"
 #include "base/basictypes.h"
+#include "base/dynamic_annotations.h"
 
 namespace base {
 
@@ -96,6 +97,14 @@ class LazyInstance : public LazyInstanceHelper {
     if (base::subtle::NoBarrier_Load(&state_) != STATE_CREATED)
       EnsureInstance(instance, Traits::New, Traits::Delete);
 
+    // This annotation helps race detectors recognize correct lock-less
+    // synchronization between different threads calling Pointer().
+    // We suggest dynamic race detection tool that
+    // "ctor(instance)" in EnsureInstance(...) happens before
+    // "return instance" in Pointer().
+    // See the corresponding HAPPENS_BEFORE in EnsureInstance(...).
+    ANNOTATE_HAPPENS_AFTER(&state_);
+
     return instance;
   }