[libc++] Tolerate presence of __deallocate macro

Summary:
On Windows the identifier `__deallocate` is defined as a macro by one of the Windows system headers. Previously libc++ worked around this by `#undef __deallocate` and generating a warning. However this causes the WIN32 version of `__threading_support` to always generate a warning on Windows. This is not OK.

This patch renames all usages of `__deallocate` internally as to not conflict with the macro.

Reviewers: mclow.lists, majnemer, rnk, rsmith, smeenai, compnerd

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D28426

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@291332 91177308-0d34-0410-b5e6-96231b3b80d8

include/experimental/dynarray

@@ -11,9 +11,6 @@
 #ifndef _LIBCPP_DYNARRAY
 #define _LIBCPP_DYNARRAY
 
-#include <__config>
-#if _LIBCPP_STD_VER > 11
-
 /*
     dynarray synopsis
 
@@ -96,6 +93,8 @@ public:
 }}  // std::experimental
 
 */
+#include <__config>
+#if _LIBCPP_STD_VER > 11
 
 #include <__functional_base>
 #include <iterator>
@@ -104,8 +103,6 @@ public:
 #include <new>
 #include <algorithm>
 
-#include <__undef___deallocate>
-
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
@@ -143,9 +140,9 @@ private:
         return static_cast<value_type *> (_VSTD::__allocate (sizeof(value_type) * count));
     }
 
-    static inline _LIBCPP_INLINE_VISIBILITY void __deallocate ( value_type* __ptr ) noexcept
+    static inline _LIBCPP_INLINE_VISIBILITY void __deallocate_value( value_type* __ptr ) noexcept
     {
-        _VSTD::__deallocate (static_cast<void *> (__ptr));
+        _VSTD::__libcpp_deallocate (static_cast<void *> (__ptr));
     }
 
 public:
@@ -265,7 +262,7 @@ dynarray<_Tp>::~dynarray()
     value_type *__data = data () + __size_;
     for ( size_t i = 0; i < __size_; ++i )
         (--__data)->value_type::~value_type();
-    __deallocate ( __base_ );
+    __deallocate_value( __base_ );
 }
 
 template <class _Tp>