diff options
| author | Eric Fiselier <eric@efcs.ca> | 2017-01-21 00:02:12 +0000 |
|---|---|---|
| committer | Eric Fiselier <eric@efcs.ca> | 2017-01-21 00:02:12 +0000 |
| commit | 952eaecfc6fa504c40d6f7220d8c017d014cda0c (patch) | |
| tree | 91f54ab548a1a5a8c94abc48bbc864bd2ed76c7a /include/optional | |
| parent | ee856f131dc433ff3c7522a4782aed7ac6de4f4a (diff) | |
Implement P0513R0 - "Poisoning the Hash"
Summary:
Exactly what the title says.
This patch also adds a `std::hash<nullptr_t>` specialization in C++17, but it was not added by this paper and I can't find the actual paper that adds it.
See http://wg21.link/P0513R0 for more info.
If there are no comments in the next couple of days I'll commit this
Reviewers: mclow.lists, K-ballo, EricWF
Reviewed By: EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D28938
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@292684 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'include/optional')
| -rw-r--r-- | include/optional | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/include/optional b/include/optional index c002cc729..b13a2d5f7 100644 --- a/include/optional +++ b/include/optional @@ -1295,7 +1295,9 @@ optional<_Tp> make_optional(initializer_list<_Up> __il, _Args&&... __args) } template <class _Tp> -struct _LIBCPP_TEMPLATE_VIS hash<optional<_Tp> > +struct _LIBCPP_TEMPLATE_VIS hash< + __enable_hash_helper<optional<_Tp>, remove_const_t<_Tp>> +> { typedef optional<_Tp> argument_type; typedef size_t result_type; @@ -1303,7 +1305,7 @@ struct _LIBCPP_TEMPLATE_VIS hash<optional<_Tp> > _LIBCPP_INLINE_VISIBILITY result_type operator()(const argument_type& __opt) const _NOEXCEPT { - return static_cast<bool>(__opt) ? hash<_Tp>()(*__opt) : 0; + return static_cast<bool>(__opt) ? hash<remove_const_t<_Tp>>()(*__opt) : 0; } }; |