LWG Issue 2162: mark allocator_traits::maxsize as noexcept

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@189399 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/memory b/include/memory
index 49a53c3..189e3b9 100644
--- a/include/memory
+++ b/include/memory
@@ -90,7 +90,7 @@
     template <class T>
         static void destroy(allocator_type& a, T* p);
 
-    static size_type max_size(const allocator_type& a);
+    static size_type max_size(const allocator_type& a); // noexcept in C++14
 
     static allocator_type
         select_on_container_copy_construction(const allocator_type& a);
@@ -1483,7 +1483,7 @@
             {__destroy(__has_destroy<allocator_type, _Tp*>(), __a, __p);}
 
     _LIBCPP_INLINE_VISIBILITY
-    static size_type max_size(const allocator_type& __a)
+    static size_type max_size(const allocator_type& __a) _NOEXCEPT
         {return __max_size(__has_max_size<const allocator_type>(), __a);}
 
     _LIBCPP_INLINE_VISIBILITY