Disable scoped_refptr operator T* on Linux.

base/memory/ref_counted.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_MEMORY_REF_COUNTED_H_
 #define BASE_MEMORY_REF_COUNTED_H_
 
 #include <cassert>
 
 #include "base/atomic_ref_count.h"
 #include "base/base_export.h"
 #include "base/compiler_specific.h"
 #ifndef NDEBUG
 #include "base/logging.h"
 #endif
 #include "base/threading/thread_collision_warner.h"
 
+#if defined(OS_LINUX)

[Ryan Sleevi, 2014/09/04 21:29:04]

1) Shouldn't you explicitly include build/build_config.h ?
2) This includes ChromeOS, doesn't it?

[dcheng, 2014/09/04 21:36:17]

1) Done.
2) I thought they were mutually exclusive. A random comment in
https://code.google.com/p/chromium/codesearch#chromium/src/base/linux_util.cc...
leaves me to believe this is the case. I'll run this patch through the CrOS
trybots to see what happens.

+#define DISABLE_SCOPED_REFPTR_CONVERSION_OPERATOR
+#endif
+
 namespace base {
 
 namespace subtle {
 
 class BASE_EXPORT RefCountedBase {
  public:
   bool HasOneRef() const { return ref_count_ == 1; }
 
  protected:
   RefCountedBase()
@@ skipping 256 matching lines @@
       ptr_->AddRef();
   }
 
   ~scoped_refptr() {
     if (ptr_)
       ptr_->Release();
   }
 
   T* get() const { return ptr_; }
 
+#if !defined(DISABLE_SCOPED_REFPTR_CONVERSION_OPERATOR)
   // Allow scoped_refptr<C> to be used in boolean expression
   // and comparison operations.
   operator T*() const { return ptr_; }
+#endif
 
   T& operator*() const {
     assert(ptr_ != NULL);
     return *ptr_;
   }
 
   T* operator->() const {
     assert(ptr_ != NULL);
     return ptr_;
   }
@@ skipping 21 matching lines @@
   void swap(T** pp) {
     T* p = ptr_;
     ptr_ = *pp;
     *pp = p;
   }
 
   void swap(scoped_refptr<T>& r) {
     swap(&r.ptr_);
   }
 
+#if defined(DISABLE_SCOPED_REFPTR_CONVERSION_OPERATOR)
+  template <typename U>
+  bool operator==(const scoped_refptr<U>& rhs) const {
+    return ptr_ == rhs.get();
+  }
+
+  template <typename U>
+  bool operator!=(const scoped_refptr<U>& rhs) const {
+    return !operator==(rhs);
+  }
+
+  template <typename U>
+  bool operator<(const scoped_refptr<U>& rhs) const {
+    return ptr_ < rhs.get();
+  }
+#endif
+
  protected:
   T* ptr_;
 };
 
 // Handy utility for creating a scoped_refptr<T> out of a T* explicitly without
 // having to retype all the template arguments
 template <typename T>
 scoped_refptr<T> make_scoped_refptr(T* t) {
   return scoped_refptr<T>(t);
 }
 
+#if defined(DISABLE_SCOPED_REFPTR_CONVERSION_OPERATOR)
+// Temporary operator overloads to facilitate the transition...
+template <typename T, typename U>
+bool operator==(const scoped_refptr<T>& lhs, const U* rhs) {
+  return lhs.get() == rhs;
+}
+
+template <typename T, typename U>
+bool operator==(const T* lhs, const scoped_refptr<U>& rhs) {
+  return lhs == rhs.get();
+}
+
+template <typename T, typename U>
+bool operator!=(const scoped_refptr<T>& lhs, const U* rhs) {
+  return !operator==(lhs, rhs);
+}
+
+template <typename T, typename U>
+bool operator!=(const T* lhs, const scoped_refptr<U>& rhs) {
+  return !operator==(lhs, rhs);
+}
+
+template <typename T>
+std::ostream& operator<<(std::ostream& out, const scoped_refptr<T>& p) {

[Ryan Sleevi, 2014/08/28 18:42:51]

Don't you need iosfwd included when NDEBUG isn't set (because you don't have
base/logging.h included)

[dcheng, 2014/09/04 21:36:17]

Done.

+  return out << p.get();
+}
+#endif  // defined(DISABLE_SCOPED_REFPTR_CONVERSION_OPERATOR)
+
 #endif  // BASE_MEMORY_REF_COUNTED_H_