1 files changed, 17 insertions, 6 deletions
diff --git a/base/memory/singleton.h b/base/memory/singleton.h
index 79e4441a8e..5c58d5fe29 100644
--- a/base/memory/singleton.h
+++ b/base/memory/singleton.h
@@ -22,6 +22,7 @@
 #include "base/at_exit.h"
 #include "base/atomicops.h"
 #include "base/base_export.h"
+#include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/aligned_memory.h"
 #include "base/threading/thread_restrictions.h"
@@ -63,7 +64,7 @@ struct DefaultSingletonTraits {
   // exit. See below for the required call that makes this happen.
   static const bool kRegisterAtExit = true;
 
-#ifndef NDEBUG
+#if DCHECK_IS_ON()
   // Set to false to disallow access on a non-joinable thread.  This is
   // different from kRegisterAtExit because StaticMemorySingletonTraits allows
   // access on non-joinable threads, and gracefully handles this.
@@ -78,7 +79,7 @@ struct DefaultSingletonTraits {
 template<typename Type>
 struct LeakySingletonTraits : public DefaultSingletonTraits<Type> {
   static const bool kRegisterAtExit = false;
-#ifndef NDEBUG
+#if DCHECK_IS_ON()
   static const bool kAllowedToAccessOnNonjoinableThread = true;
 #endif
 };
@@ -152,14 +153,17 @@ subtle::Atomic32 StaticMemorySingletonTraits<Type>::dead_ = 0;
 // Example usage:
 //
 // In your header:
-//   template <typename T> struct DefaultSingletonTraits;
+//   namespace base {
+//   template <typename T>
+//   struct DefaultSingletonTraits;
+//   }
 //   class FooClass {
 //    public:
 //     static FooClass* GetInstance();  <-- See comment below on this.
 //     void Bar() { ... }
 //    private:
 //     FooClass() { ... }
-//     friend struct DefaultSingletonTraits<FooClass>;
+//     friend struct base::DefaultSingletonTraits<FooClass>;
 //
 //     DISALLOW_COPY_AND_ASSIGN(FooClass);
 //   };
@@ -167,7 +171,14 @@ subtle::Atomic32 StaticMemorySingletonTraits<Type>::dead_ = 0;
 // In your source file:
 //  #include "base/memory/singleton.h"
 //  FooClass* FooClass::GetInstance() {
-//    return Singleton<FooClass>::get();
+//    return base::Singleton<FooClass>::get();
+//  }
+//
+// Or for leaky singletons:
+//  #include "base/memory/singleton.h"
+//  FooClass* FooClass::GetInstance() {
+//    return base::Singleton<
+//        FooClass, base::LeakySingletonTraits<FooClass>>::get();
 //  }
 //
 // And to call methods on FooClass:
@@ -227,7 +238,7 @@ class Singleton {
 
   // Return a pointer to the one true instance of the class.
   static Type* get() {
-#ifndef NDEBUG
+#if DCHECK_IS_ON()
     // Avoid making TLS lookup on release builds.
     if (!Traits::kAllowedToAccessOnNonjoinableThread)
       ThreadRestrictions::AssertSingletonAllowed();