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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: clang-8
// constexpr destructors are only supported starting with gcc 10
// UNSUPPORTED: gcc-8, gcc-9
// <memory>
// template <class Alloc>
// struct allocator_traits
// {
// template <class Ptr>
// static constexpr void destroy(allocator_type& a, Ptr p);
// ...
// };
#include <memory>
#include <cassert>
#include <cstddef>
#include "test_macros.h"
#include "incomplete_type_helper.h"
template <class T>
struct NoDestroy
{
typedef T value_type;
TEST_CONSTEXPR_CXX20 T* allocate(std::size_t n)
{
return std::allocator<T>().allocate(n);
}
TEST_CONSTEXPR_CXX20 void deallocate(T* p, std::size_t n)
{
return std::allocator<T>().deallocate(p, n);
}
};
template <class T>
struct CountDestroy
{
TEST_CONSTEXPR explicit CountDestroy(int* counter)
: counter_(counter)
{ }
typedef T value_type;
TEST_CONSTEXPR_CXX20 T* allocate(std::size_t n)
{
return std::allocator<T>().allocate(n);
}
TEST_CONSTEXPR_CXX20 void deallocate(T* p, std::size_t n)
{
return std::allocator<T>().deallocate(p, n);
}
template <class U>
TEST_CONSTEXPR_CXX20 void destroy(U* p)
{
++*counter_;
p->~U();
}
int* counter_;
};
struct CountDestructor
{
TEST_CONSTEXPR explicit CountDestructor(int* counter)
: counter_(counter)
{ }
TEST_CONSTEXPR_CXX20 ~CountDestructor() { ++*counter_; }
int* counter_;
};
TEST_CONSTEXPR_CXX20 bool test()
{
{
typedef NoDestroy<CountDestructor> Alloc;
int destructors = 0;
Alloc alloc;
CountDestructor* pool = std::allocator_traits<Alloc>::allocate(alloc, 1);
std::allocator_traits<Alloc>::construct(alloc, pool, &destructors);
assert(destructors == 0);
std::allocator_traits<Alloc>::destroy(alloc, pool);
assert(destructors == 1);
std::allocator_traits<Alloc>::deallocate(alloc, pool, 1);
}
{
typedef IncompleteHolder* T;
typedef NoDestroy<T> Alloc;
Alloc alloc;
T* pool = std::allocator_traits<Alloc>::allocate(alloc, 1);
std::allocator_traits<Alloc>::construct(alloc, pool, nullptr);
std::allocator_traits<Alloc>::destroy(alloc, pool);
std::allocator_traits<Alloc>::deallocate(alloc, pool, 1);
}
{
typedef CountDestroy<CountDestructor> Alloc;
int destroys_called = 0;
int destructors_called = 0;
Alloc alloc(&destroys_called);
CountDestructor* pool = std::allocator_traits<Alloc>::allocate(alloc, 1);
std::allocator_traits<Alloc>::construct(alloc, pool, &destructors_called);
assert(destroys_called == 0);
assert(destructors_called == 0);
std::allocator_traits<Alloc>::destroy(alloc, pool);
assert(destroys_called == 1);
assert(destructors_called == 1);
std::allocator_traits<Alloc>::deallocate(alloc, pool, 1);
}
return true;
}
int main(int, char**)
{
test();
#if TEST_STD_VER > 17
static_assert(test());
#endif
return 0;
}
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