Assert sequence validity on non-thread-safe RefCount manipulations (2)

base/memory/ref_counted.cc

Index: base/memory/ref_counted.cc
diff --git a/base/memory/ref_counted.cc b/base/memory/ref_counted.cc
index cd6181b147349e46c4a86b7487e952d4725d1f91..5ca42c562dc7582cfcbfa44621a310932f838237 100644
--- a/base/memory/ref_counted.cc
+++ b/base/memory/ref_counted.cc
@@ -3,9 +3,17 @@
 // found in the LICENSE file.
 
 #include "base/memory/ref_counted.h"
+
 #include "base/threading/thread_collision_warner.h"
 
 namespace base {
+namespace {
+
+#if DCHECK_IS_ON()
+AtomicRefCount g_cross_thread_ref_count_access_allow_count = 0;
+#endif
+
+}  // namespace
 
 namespace subtle {
 
@@ -48,6 +56,23 @@ bool RefCountedThreadSafeBase::Release() const {
   return false;
 }
 
+#if DCHECK_IS_ON()
+bool RefCountedBase::CalledOnValidSequence() const {
+  return !AtomicRefCountIsZero(&g_cross_thread_ref_count_access_allow_count) ||
+         sequence_checker_.CalledOnValidSequence();

[gab, 2017/02/17 21:10:40]

Flip these (i.e. sequence check || exception).

[tzik, 2017/02/21 06:15:02]

Done.

+}
+#endif
+
 }  // namespace subtle
 
+#if DCHECK_IS_ON()
+ScopedAllowCrossThreadRefCountAccess::ScopedAllowCrossThreadRefCountAccess() {
+  AtomicRefCountInc(&g_cross_thread_ref_count_access_allow_count);
+}
+
+ScopedAllowCrossThreadRefCountAccess::~ScopedAllowCrossThreadRefCountAccess() {
+  AtomicRefCountDec(&g_cross_thread_ref_count_access_allow_count);
+}
+#endif
+
 }  // namespace base