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52ddb5e2b8
Summary: P1006 adds support for constexpr in the specialization of pointer_traits for raw pointers. This is necessary in order to use pointer_traits in the upcoming constexpr containers. We expect P1006 to be voted into the working draft for C++20 at the San Diego meeting. Reviewers: mclow.lists, EricWF Subscribers: christof, dexonsmith, libcxx-commits Differential Revision: https://reviews.llvm.org/D53867 git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@346764 91177308-0d34-0410-b5e6-96231b3b80d8
45 lines
1.0 KiB
C++
45 lines
1.0 KiB
C++
//===----------------------------------------------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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// <memory>
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// template <class T>
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// struct pointer_traits<T*>
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// {
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// static pointer pointer_to(<details>); // constexpr in C++20
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// ...
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// };
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#include <memory>
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#include <cassert>
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#include "test_macros.h"
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#if TEST_STD_VER > 17
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constexpr
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#endif
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bool check() {
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{
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int i = 0;
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static_assert((std::is_same<int *, decltype(std::pointer_traits<int*>::pointer_to(i))>::value), "");
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int* a = std::pointer_traits<int*>::pointer_to(i);
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assert(a == &i);
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}
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{
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(std::pointer_traits<void*>::element_type)0;
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}
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return true;
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}
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int main() {
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check();
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#if TEST_STD_VER > 17
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static_assert(check(), "");
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#endif
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}
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