test/std/thread/futures/futures.tas/futures.task.members/ctor2.fail.cpp

//===----------------------------------------------------------------------===//
//
//                     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.
//
//===----------------------------------------------------------------------===//
//
// UNSUPPORTED: libcpp-has-no-threads
// UNSUPPORTED: c++98, c++03

// <future>

// class packaged_task<R(ArgTypes...)>
// template <class F, class Allocator>
//   packaged_task(allocator_arg_t, const Allocator& a, F&& f);
// These constructors shall not participate in overload resolution if 
//    decay<F>::type is the same type as std::packaged_task<R(ArgTypes...)>.

#include <future>
#include <cassert>

#include "test_allocator.h"

struct A {};
typedef std::packaged_task<A(int, char)> PT;
typedef volatile std::packaged_task<A(int, char)> VPT;

int main()
{
    PT p { std::allocator_arg_t{}, test_allocator<A>{}, VPT {}}; // expected-error {{no matching constructor for initialization of 'PT' (aka 'packaged_task<A (int, char)>')}}
    // expected-note@future:* 1 {{candidate template ignored: disabled by 'enable_if'}}
}