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//===----------------------------------------------------------------------===//
//
// 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.
//
//===----------------------------------------------------------------------===//
// <memory>
// template <class Alloc>
// struct allocator_traits
// {
// template <class Ptr, class... Args>
// static void construct(allocator_type& a, Ptr p, Args&&... args);
// ...
// };
#include <memory>
#include <new>
#include <type_traits>
#include <cassert>
template <class T>
struct A
{
typedef T value_type;
};
int b_construct = 0;
template <class T>
struct B
{
typedef T value_type;
#ifndef _LIBCPP_HAS_NO_VARIADICS
template <class U, class ...Args>
void construct(U* p, Args&& ...args)
{
++b_construct;
::new ((void*)p) U(std::forward<Args>(args)...);
}
#endif // _LIBCPP_HAS_NO_VARIADICS
};
struct A0
{
static int count;
A0() {++count;}
};
int A0::count = 0;
struct A1
{
static int count;
A1(char c)
{
assert(c == 'c');
++count;
}
};
int A1::count = 0;
struct A2
{
static int count;
A2(char c, int i)
{
assert(c == 'd');
assert(i == 5);
++count;
}
};
int A2::count = 0;
int main()
{
{
A0::count = 0;
A<int> a;
std::aligned_storage<sizeof(A0)>::type a0;
assert(A0::count == 0);
std::allocator_traits<A<int> >::construct(a, (A0*)&a0);
assert(A0::count == 1);
}
{
A1::count = 0;
A<int> a;
std::aligned_storage<sizeof(A1)>::type a1;
assert(A1::count == 0);
std::allocator_traits<A<int> >::construct(a, (A1*)&a1, 'c');
assert(A1::count == 1);
}
{
A2::count = 0;
A<int> a;
std::aligned_storage<sizeof(A2)>::type a2;
assert(A2::count == 0);
std::allocator_traits<A<int> >::construct(a, (A2*)&a2, 'd', 5);
assert(A2::count == 1);
}
#ifndef _LIBCPP_HAS_NO_VARIADICS
{
A0::count = 0;
b_construct = 0;
B<int> b;
std::aligned_storage<sizeof(A0)>::type a0;
assert(A0::count == 0);
assert(b_construct == 0);
std::allocator_traits<B<int> >::construct(b, (A0*)&a0);
assert(A0::count == 1);
assert(b_construct == 1);
}
{
A1::count = 0;
b_construct = 0;
B<int> b;
std::aligned_storage<sizeof(A1)>::type a1;
assert(A1::count == 0);
assert(b_construct == 0);
std::allocator_traits<B<int> >::construct(b, (A1*)&a1, 'c');
assert(A1::count == 1);
assert(b_construct == 1);
}
{
A2::count = 0;
b_construct = 0;
B<int> b;
std::aligned_storage<sizeof(A2)>::type a2;
assert(A2::count == 0);
assert(b_construct == 0);
std::allocator_traits<B<int> >::construct(b, (A2*)&a2, 'd', 5);
assert(A2::count == 1);
assert(b_construct == 1);
}
#endif // _LIBCPP_HAS_NO_VARIADICS
}
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