Add assert() for scoped_refptr<T>::operator->()

base/memory/ref_counted.h

Index: base/memory/ref_counted.h
diff --git a/base/memory/ref_counted.h b/base/memory/ref_counted.h
index b7cb5e064175466d747e5ae66125262d8f1558cf..cf8ff1688dc7f4de093f78d15a17a1fade0ed0fe 100644
--- a/base/memory/ref_counted.h
+++ b/base/memory/ref_counted.h
@@ -6,6 +6,8 @@
 #define BASE_MEMORY_REF_COUNTED_H_
 #pragma once
 
+#include <cassert>
+
 #include "base/atomic_ref_count.h"
 #include "base/base_export.h"
 #include "base/threading/thread_collision_warner.h"
@@ -243,7 +245,10 @@ class scoped_refptr {
 
   T* get() const { return ptr_; }
   operator T*() const { return ptr_; }
-  T* operator->() const { return ptr_; }
+  T* operator->() const {
+    assert(ptr_ != NULL);

[jar (doing other things), 2012/01/28 02:47:22]

Could you clarify when this would be significant?

I'd assume that the result of this operator would be immediately deref'ed, to
get to some slot. I'd then expect it to segv.  Hence, the assert would be a
debug-only warning that the code is about to crash.

What caller-usage pattern am I missing?

+    return ptr_;
+  }
 
   // Release a pointer.
   // The return value is the current pointer held by this object.