Handle function name conflicts in _LIBCPP_MSVCRT mode

Visual Studio's SAL extension uses a macro named __deallocate. This macro is
used pervasively, and gets included through various different ways. This
conflicts with the similarly named interfaces in libc++. Introduce a undef
header similar to __undef_min_max to handle this. This fixes a number of errors
due to the macro replacing the function name.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@229162 91177308-0d34-0410-b5e6-96231b3b80d8

include/__hash_table

@@ -19,6 +19,7 @@
 #include <cmath>
 
 #include <__undef_min_max>
+#include <__undef___deallocate>
 
 #include <__debug>
 

include/__sso_allocator

@@ -15,6 +15,8 @@
 #include <type_traits>
 #include <new>
 
+#include <__undef___deallocate>
+
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif

include/__undef___deallocate

@@ -0,0 +1,18 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifdef __deallocate
+#if defined(_MSC_VER) && !defined(__clang__)
+_LIBCPP_WARNING("macro __deallocate is incompatible with C++.  #undefining __deallocate")
+#else
+#warning: macro __deallocate is incompatible with C++.  #undefining __deallocate
+#endif
+#undef __deallocate
+#endif

include/experimental/dynarray

@@ -104,6 +104,8 @@ public:
 #include <new>
 #include <algorithm>
 
+#include <__undef___deallocate>
+
 #if defined(_LIBCPP_NO_EXCEPTIONS)
     #include <cassert>
 #endif

include/memory

@@ -615,6 +615,7 @@ void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
 #endif
 
 #include <__undef_min_max>
+#include <__undef___deallocate>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header

include/module.modulemap

@@ -469,4 +469,5 @@ module std [system] {
   module __tree { header "__tree" export * }
   module __tuple { header "__tuple" export * }
   module __undef_min_max { header "__undef_min_max" export * }
+  module __undef___deallocate { header "__undef___deallocate" export * }
 }

include/new

@@ -68,6 +68,8 @@ void  operator delete[](void* ptr, void*) noexcept;
 #include <exception>
 #include <cstddef>
 
+#include <__undef___deallocate>
+
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif

include/valarray

@@ -348,6 +348,7 @@ template <class T> unspecified2 end(const valarray<T>& v);
 #include <new>
 
 #include <__undef_min_max>
+#include <__undef___deallocate>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header