Fix location of invocable check for unique_ptr deleter

The deleter only needs to be invocable when the unique_ptr destructor
and reset member function are instantiated. In other contexts it might
not be possible to pass unique_ptr<T, D>::pointer to the deleter, if
that requires a derived-to-base conversion from T* and T is incomplete.

	* include/bits/unique_ptr.h (__uniq_ptr_impl): Remove static assertion
	checking invocable condition.
	(unique_ptr::~unique_ptr, unique_ptr::reset): Restore static assertion
	here, where types must be complete. Pass pointer to deleter as an
	rvalue.
	* testsuite/20_util/unique_ptr/requirements/incomplete.cc: New test.

From-SVN: r264399
This commit is contained in:
Jonathan Wakely 2018-09-18 17:05:36 +01:00 committed by Jonathan Wakely
parent f96c8666f5
commit a12c16de52
3 changed files with 48 additions and 4 deletions

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@ -1,3 +1,12 @@
2018-09-18 Jonathan Wakely <jwakely@redhat.com>
* include/bits/unique_ptr.h (__uniq_ptr_impl): Remove static assertion
checking invocable condition.
(unique_ptr::~unique_ptr, unique_ptr::reset): Restore static assertion
here, where types must be complete. Pass pointer to deleter as an
rvalue.
* testsuite/20_util/unique_ptr/requirements/incomplete.cc: New test.
2018-09-13 Jonathan Wakely <jwakely@redhat.com>
* include/std/variant (variant) [__clang__]: Limit workaround to

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@ -142,8 +142,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
static_assert( !is_rvalue_reference<_Dp>::value,
"unique_ptr's deleter type must be a function object type"
" or an lvalue reference type" );
static_assert( __is_invocable<_Dp&, pointer&>::value,
"unique_ptr's deleter must be invocable with a pointer" );
__uniq_ptr_impl() = default;
__uniq_ptr_impl(pointer __p) : _M_t() { _M_ptr() = __p; }
@ -282,9 +280,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
/// Destructor, invokes the deleter if the stored pointer is not null.
~unique_ptr() noexcept
{
static_assert(__is_invocable<deleter_type&, pointer>::value,
"unique_ptr's deleter must be invocable with a pointer");
auto& __ptr = _M_t._M_ptr();
if (__ptr != nullptr)
get_deleter()(__ptr);
get_deleter()(std::move(__ptr));
__ptr = pointer();
}
@ -389,10 +389,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
void
reset(pointer __p = pointer()) noexcept
{
static_assert(__is_invocable<deleter_type&, pointer>::value,
"unique_ptr's deleter must be invocable with a pointer");
using std::swap;
swap(_M_t._M_ptr(), __p);
if (__p != pointer())
get_deleter()(__p);
get_deleter()(std::move(__p));
}
/// Exchange the pointer and deleter with another object.

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@ -0,0 +1,33 @@
// Copyright (C) 2018 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// { dg-do compile { target c++11 } }
#include <memory>
struct Base; // incomplete
struct BaseDeleter {
void operator()(Base*) const;
};
struct Derived; // incomplete
struct X {
std::unique_ptr<Derived, BaseDeleter> p;
~X(); // defined elsewhere, where Derived is complete
};