From 6f7cb576891834f1dcd87e66a32e869b82602151 Mon Sep 17 00:00:00 2001
From: Xidorn Quan <quanxunzhen@gmail.com>
Date: Thu, 20 Aug 2015 10:30:10 +1000
Subject: [PATCH] Bug 1196050 - Replace NSCAP_Zero usage with
 decltype(nullptr). r=froydnj

---
 parser/html/nsHtml5RefPtr.h | 20 +++++++----------
 xpcom/base/nsAutoPtr.h      | 44 +++++++++++++++----------------------
 xpcom/glue/nsCOMPtr.h       | 24 ++++++++------------
 3 files changed, 35 insertions(+), 53 deletions(-)

diff --git a/parser/html/nsHtml5RefPtr.h b/parser/html/nsHtml5RefPtr.h
index 17fffae9cb5..89e56924811 100644
--- a/parser/html/nsHtml5RefPtr.h
+++ b/parser/html/nsHtml5RefPtr.h
@@ -417,37 +417,33 @@ operator!=( U* lhs, const nsHtml5RefPtr<T>& rhs )
 template <class T>
 inline
 bool
-operator==( const nsHtml5RefPtr<T>& lhs, NSCAP_Zero* rhs )
-    // specifically to allow |smartPtr == 0|
+operator==( const nsHtml5RefPtr<T>& lhs, decltype(nullptr) )
   {
-    return static_cast<const void*>(lhs.get()) == reinterpret_cast<const void*>(rhs);
+    return lhs.get() == nullptr;
   }
 
 template <class T>
 inline
 bool
-operator==( NSCAP_Zero* lhs, const nsHtml5RefPtr<T>& rhs )
-    // specifically to allow |0 == smartPtr|
+operator==( decltype(nullptr), const nsHtml5RefPtr<T>& rhs )
   {
-    return reinterpret_cast<const void*>(lhs) == static_cast<const void*>(rhs.get());
+    return nullptr == rhs.get();
   }
 
 template <class T>
 inline
 bool
-operator!=( const nsHtml5RefPtr<T>& lhs, NSCAP_Zero* rhs )
-    // specifically to allow |smartPtr != 0|
+operator!=( const nsHtml5RefPtr<T>& lhs, decltype(nullptr) )
   {
-    return static_cast<const void*>(lhs.get()) != reinterpret_cast<const void*>(rhs);
+    return lhs.get() != nullptr;
   }
 
 template <class T>
 inline
 bool
-operator!=( NSCAP_Zero* lhs, const nsHtml5RefPtr<T>& rhs )
-    // specifically to allow |0 != smartPtr|
+operator!=( decltype(nullptr), const nsHtml5RefPtr<T>& rhs )
   {
-    return reinterpret_cast<const void*>(lhs) != static_cast<const void*>(rhs.get());
+    return nullptr != rhs.get();
   }
 
 #endif // !defined(nsHtml5RefPtr_h)
diff --git a/xpcom/base/nsAutoPtr.h b/xpcom/base/nsAutoPtr.h
index c2f53314a32..eaaaf90e175 100644
--- a/xpcom/base/nsAutoPtr.h
+++ b/xpcom/base/nsAutoPtr.h
@@ -414,38 +414,34 @@ operator!=(U* aLhs, const nsAutoPtr<T>& aRhs)
 
 
 
-// Comparing an |nsAutoPtr| to |0|
+// Comparing an |nsAutoPtr| to |nullptr|
 
 template <class T>
 inline bool
-operator==(const nsAutoPtr<T>& aLhs, NSCAP_Zero* aRhs)
-// specifically to allow |smartPtr == 0|
+operator==(const nsAutoPtr<T>& aLhs, decltype(nullptr))
 {
-  return static_cast<const void*>(aLhs.get()) == reinterpret_cast<const void*>(aRhs);
+  return aLhs.get() == nullptr;
 }
 
 template <class T>
 inline bool
-operator==(NSCAP_Zero* aLhs, const nsAutoPtr<T>& aRhs)
-// specifically to allow |0 == smartPtr|
+operator==(decltype(nullptr), const nsAutoPtr<T>& aRhs)
 {
-  return reinterpret_cast<const void*>(aLhs) == static_cast<const void*>(aRhs.get());
+  return nullptr == aRhs.get();
 }
 
 template <class T>
 inline bool
-operator!=(const nsAutoPtr<T>& aLhs, NSCAP_Zero* aRhs)
-// specifically to allow |smartPtr != 0|
+operator!=(const nsAutoPtr<T>& aLhs, decltype(nullptr))
 {
-  return static_cast<const void*>(aLhs.get()) != reinterpret_cast<const void*>(aRhs);
+  return aLhs.get() != nullptr;
 }
 
 template <class T>
 inline bool
-operator!=(NSCAP_Zero* aLhs, const nsAutoPtr<T>& aRhs)
-// specifically to allow |0 != smartPtr|
+operator!=(decltype(nullptr), const nsAutoPtr<T>& aRhs)
 {
-  return reinterpret_cast<const void*>(aLhs) != static_cast<const void*>(aRhs.get());
+  return nullptr != aRhs.get();
 }
 
 
@@ -766,38 +762,34 @@ operator!=(U* aLhs, const nsAutoArrayPtr<T>& aRhs)
 
 
 
-// Comparing an |nsAutoArrayPtr| to |0|
+// Comparing an |nsAutoArrayPtr| to |nullptr|
 
 template <class T>
 inline bool
-operator==(const nsAutoArrayPtr<T>& aLhs, NSCAP_Zero* aRhs)
-// specifically to allow |smartPtr == 0|
+operator==(const nsAutoArrayPtr<T>& aLhs, decltype(nullptr))
 {
-  return static_cast<const void*>(aLhs.get()) == reinterpret_cast<const void*>(aRhs);
+  return aLhs.get() == nullptr;
 }
 
 template <class T>
 inline bool
-operator==(NSCAP_Zero* aLhs, const nsAutoArrayPtr<T>& aRhs)
-// specifically to allow |0 == smartPtr|
+operator==(decltype(nullptr), const nsAutoArrayPtr<T>& aRhs)
 {
-  return reinterpret_cast<const void*>(aLhs) == static_cast<const void*>(aRhs.get());
+  return nullptr == aRhs.get();
 }
 
 template <class T>
 inline bool
-operator!=(const nsAutoArrayPtr<T>& aLhs, NSCAP_Zero* aRhs)
-// specifically to allow |smartPtr != 0|
+operator!=(const nsAutoArrayPtr<T>& aLhs, decltype(nullptr))
 {
-  return static_cast<const void*>(aLhs.get()) != reinterpret_cast<const void*>(aRhs);
+  return aLhs.get() != nullptr;
 }
 
 template <class T>
 inline bool
-operator!=(NSCAP_Zero* aLhs, const nsAutoArrayPtr<T>& aRhs)
-// specifically to allow |0 != smartPtr|
+operator!=(decltype(nullptr), const nsAutoArrayPtr<T>& aRhs)
 {
-  return reinterpret_cast<const void*>(aLhs) != static_cast<const void*>(aRhs.get());
+  return nullptr != aRhs.get();
 }
 
 
diff --git a/xpcom/glue/nsCOMPtr.h b/xpcom/glue/nsCOMPtr.h
index 4758021b2f5..406e7836cda 100644
--- a/xpcom/glue/nsCOMPtr.h
+++ b/xpcom/glue/nsCOMPtr.h
@@ -1350,40 +1350,34 @@ operator!=(U* aLhs, const nsCOMPtr<T>& aRhs)
 
 
 
-// Comparing an |nsCOMPtr| to |0|
+// Comparing an |nsCOMPtr| to |nullptr|
 
-class NSCAP_Zero;
-
-// Specifically to allow |smartPtr == 0|.
 template<class T>
 inline bool
-operator==(const nsCOMPtr<T>& aLhs, NSCAP_Zero* aRhs)
+operator==(const nsCOMPtr<T>& aLhs, decltype(nullptr))
 {
-  return static_cast<const void*>(aLhs.get()) == reinterpret_cast<const void*>(aRhs);
+  return aLhs.get() == nullptr;
 }
 
-// Specifically to allow |0 == smartPtr|.
 template<class T>
 inline bool
-operator==(NSCAP_Zero* aLhs, const nsCOMPtr<T>& aRhs)
+operator==(decltype(nullptr), const nsCOMPtr<T>& aRhs)
 {
-  return reinterpret_cast<const void*>(aLhs) == static_cast<const void*>(aRhs.get());
+  return nullptr == aRhs.get();
 }
 
-// Specifically to allow |smartPtr != 0|.
 template<class T>
 inline bool
-operator!=(const nsCOMPtr<T>& aLhs, NSCAP_Zero* aRhs)
+operator!=(const nsCOMPtr<T>& aLhs, decltype(nullptr))
 {
-  return static_cast<const void*>(aLhs.get()) != reinterpret_cast<const void*>(aRhs);
+  return aLhs.get() != nullptr;
 }
 
-// Specifically to allow |0 != smartPtr|.
 template<class T>
 inline bool
-operator!=(NSCAP_Zero* aLhs, const nsCOMPtr<T>& aRhs)
+operator!=(decltype(nullptr), const nsCOMPtr<T>& aRhs)
 {
-  return reinterpret_cast<const void*>(aLhs) != static_cast<const void*>(aRhs.get());
+  return nullptr != aRhs.get();
 }