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PR libstdc++/83427 detect weak result type from noexcept functions

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PR libstdc++/83427
	* include/bits/refwrap.h (_Maybe_unary_or_binary_function): Move here
	from <bits/std_function.h>.
	(_Mem_fn_traits_base, _Mem_fn_traits): Move here, from <functional>.
	(_Weak_result_type_impl, _Reference_wrapper_base): Deduce noexcept
	for function types. Remove partial specializations for member
	functions.
	(_Weak_result_type_impl): Remove unused partial specializations for
	non-referenceable function types and for references to functions.
	(_Weak_result_type_memfun, _Reference_wrapper_base_memfun): New
	helpers to handle member functions via _Mem_fn_traits.
	(_Weak_result_type, reference_wrapper): Derive from new helpers.
	* include/bits/std_function.h (_Maybe_unary_or_binary_function): Move
	to <bits/refwrap.h>.
	* include/std/functional (_Pack, _AllConvertible, _NotSame): Remove.
	(_Mem_fn_traits_base, _Mem_fn_traits): Move to <bits/refwrap.h>.
	* testsuite/20_util/bind/83427.cc: New test.
	* testsuite/20_util/bind/refqual.cc: Add noexcept to functions and
	check for weak result types.
	* testsuite/20_util/reference_wrapper/83427.cc: New test.

From-SVN: r255651
This commit is contained in:
Jonathan Wakely 2017-12-14 17:18:22 +00:00 committed by Jonathan Wakely
parent db811328e0
commit 00677c4877
7 changed files with 209 additions and 216 deletions
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21
libstdc++-v3/ChangeLog
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@ -1,5 +1,26 @@
2017-12-14 Jonathan Wakely <jwakely@redhat.com>
PR libstdc++/83427
* include/bits/refwrap.h (_Maybe_unary_or_binary_function): Move here
from <bits/std_function.h>.
(_Mem_fn_traits_base, _Mem_fn_traits): Move here, from <functional>.
(_Weak_result_type_impl, _Reference_wrapper_base): Deduce noexcept
for function types. Remove partial specializations for member
functions.
(_Weak_result_type_impl): Remove unused partial specializations for
non-referenceable function types and for references to functions.
(_Weak_result_type_memfun, _Reference_wrapper_base_memfun): New
helpers to handle member functions via _Mem_fn_traits.
(_Weak_result_type, reference_wrapper): Derive from new helpers.
* include/bits/std_function.h (_Maybe_unary_or_binary_function): Move
to <bits/refwrap.h>.
* include/std/functional (_Pack, _AllConvertible, _NotSame): Remove.
(_Mem_fn_traits_base, _Mem_fn_traits): Move to <bits/refwrap.h>.
* testsuite/20_util/bind/83427.cc: New test.
* testsuite/20_util/bind/refqual.cc: Add noexcept to functions and
check for weak result types.
* testsuite/20_util/reference_wrapper/83427.cc: New test.
* testsuite/26_numerics/complex/inserters_extractors/char/dr2714.cc:
Add tests using noskipws.

242
libstdc++-v3/include/bits/refwrap.h
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@ -44,6 +44,69 @@ namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* Derives from @c unary_function or @c binary_function, or perhaps
* nothing, depending on the number of arguments provided. The
* primary template is the basis case, which derives nothing.
*/
template<typename _Res, typename... _ArgTypes>
struct _Maybe_unary_or_binary_function { };
/// Derives from @c unary_function, as appropriate.
template<typename _Res, typename _T1>
struct _Maybe_unary_or_binary_function<_Res, _T1>
: std::unary_function<_T1, _Res> { };
/// Derives from @c binary_function, as appropriate.
template<typename _Res, typename _T1, typename _T2>
struct _Maybe_unary_or_binary_function<_Res, _T1, _T2>
: std::binary_function<_T1, _T2, _Res> { };
template<typename _Signature>
struct _Mem_fn_traits;
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Mem_fn_traits_base
{
using __result_type = _Res;
using __maybe_type
= _Maybe_unary_or_binary_function<_Res, _Class*, _ArgTypes...>;
using __arity = integral_constant<size_t, sizeof...(_ArgTypes)>;
};
#define _GLIBCXX_MEM_FN_TRAITS2(_CV, _REF, _LVAL, _RVAL) \
template<typename _Res, typename _Class, typename... _ArgTypes> \
struct _Mem_fn_traits<_Res (_Class::*)(_ArgTypes...) _CV _REF> \
: _Mem_fn_traits_base<_Res, _CV _Class, _ArgTypes...> \
{ \
using __vararg = false_type; \
}; \
template<typename _Res, typename _Class, typename... _ArgTypes> \
struct _Mem_fn_traits<_Res (_Class::*)(_ArgTypes... ...) _CV _REF> \
: _Mem_fn_traits_base<_Res, _CV _Class, _ArgTypes...> \
{ \
using __vararg = true_type; \
};
#define _GLIBCXX_MEM_FN_TRAITS(_REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2( , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(const , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(volatile , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(const volatile, _REF, _LVAL, _RVAL)
_GLIBCXX_MEM_FN_TRAITS( , true_type, true_type)
_GLIBCXX_MEM_FN_TRAITS(&, true_type, false_type)
_GLIBCXX_MEM_FN_TRAITS(&&, false_type, true_type)
#if __cplusplus > 201402L
_GLIBCXX_MEM_FN_TRAITS(noexcept, true_type, true_type)
_GLIBCXX_MEM_FN_TRAITS(& noexcept, true_type, false_type)
_GLIBCXX_MEM_FN_TRAITS(&& noexcept, false_type, true_type)
#endif
#undef _GLIBCXX_MEM_FN_TRAITS
#undef _GLIBCXX_MEM_FN_TRAITS2
/// If we have found a result_type, extract it.
template<typename _Functor, typename = __void_t<>>
struct _Maybe_get_result_type
@ -64,101 +127,52 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{ };
/// Retrieve the result type for a function type.
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes...)>
template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
struct _Weak_result_type_impl<_Res(_ArgTypes...) _GLIBCXX_NOEXCEPT_QUAL>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes......)>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes...) const>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes......) const>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes...) volatile>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes......) volatile>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes...) const volatile>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes......) const volatile>
{ typedef _Res result_type; };
/// Retrieve the result type for a function reference.
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(&)(_ArgTypes...)>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(&)(_ArgTypes......)>
/// Retrieve the result type for a varargs function type.
template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
struct _Weak_result_type_impl<_Res(_ArgTypes......) _GLIBCXX_NOEXCEPT_QUAL>
{ typedef _Res result_type; };
/// Retrieve the result type for a function pointer.
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(*)(_ArgTypes...)>
template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
struct _Weak_result_type_impl<_Res(*)(_ArgTypes...) _GLIBCXX_NOEXCEPT_QUAL>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(*)(_ArgTypes......)>
/// Retrieve the result type for a varargs function pointer.
template<typename _Res, typename... _ArgTypes _GLIBCXX_NOEXCEPT_PARM>
struct
_Weak_result_type_impl<_Res(*)(_ArgTypes......) _GLIBCXX_NOEXCEPT_QUAL>
{ typedef _Res result_type; };
/// Retrieve result type for a member function pointer.
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...)>
{ typedef _Res result_type; };
// Let _Weak_result_type_impl perform the real work.
template<typename _Functor,
bool = is_member_function_pointer<_Functor>::value>
struct _Weak_result_type_memfun
: _Weak_result_type_impl<_Functor>
{ };
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......)>
{ typedef _Res result_type; };
// A pointer to member function has a weak result type.
template<typename _MemFunPtr>
struct _Weak_result_type_memfun<_MemFunPtr, true>
{
using result_type = typename _Mem_fn_traits<_MemFunPtr>::__result_type;
};
/// Retrieve result type for a const member function pointer.
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...) const>
{ typedef _Res result_type; };
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......) const>
{ typedef _Res result_type; };
/// Retrieve result type for a volatile member function pointer.
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...) volatile>
{ typedef _Res result_type; };
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......) volatile>
{ typedef _Res result_type; };
/// Retrieve result type for a const volatile member function pointer.
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...)
const volatile>
{ typedef _Res result_type; };
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......)
const volatile>
{ typedef _Res result_type; };
// A pointer to data member doesn't have a weak result type.
template<typename _Func, typename _Class>
struct _Weak_result_type_memfun<_Func _Class::*, false>
{ };
/**
* Strip top-level cv-qualifiers from the function object and let
* _Weak_result_type_impl perform the real work.
* _Weak_result_type_memfun perform the real work.
*/
template<typename _Functor>
struct _Weak_result_type
: _Weak_result_type_impl<typename remove_cv<_Functor>::type>
: _Weak_result_type_memfun<typename remove_cv<_Functor>::type>
{ };
// Detect nested argument_type.
@ -201,8 +215,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{ };
// - a function type (unary)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(_T1)>
template<typename _Res, typename _T1 _GLIBCXX_NOEXCEPT_PARM>
struct _Reference_wrapper_base<_Res(_T1) _GLIBCXX_NOEXCEPT_QUAL>
: unary_function<_T1, _Res>
{ };
@ -222,8 +236,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{ };
// - a function type (binary)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(_T1, _T2)>
template<typename _Res, typename _T1, typename _T2 _GLIBCXX_NOEXCEPT_PARM>
struct _Reference_wrapper_base<_Res(_T1, _T2) _GLIBCXX_NOEXCEPT_QUAL>
: binary_function<_T1, _T2, _Res>
{ };
@ -243,64 +257,28 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{ };
// - a function pointer type (unary)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(*)(_T1)>
template<typename _Res, typename _T1 _GLIBCXX_NOEXCEPT_PARM>
struct _Reference_wrapper_base<_Res(*)(_T1) _GLIBCXX_NOEXCEPT_QUAL>
: unary_function<_T1, _Res>
{ };
// - a function pointer type (binary)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(*)(_T1, _T2)>
template<typename _Res, typename _T1, typename _T2 _GLIBCXX_NOEXCEPT_PARM>
struct _Reference_wrapper_base<_Res(*)(_T1, _T2) _GLIBCXX_NOEXCEPT_QUAL>
: binary_function<_T1, _T2, _Res>
{ };
// - a pointer to member function type (unary, no qualifiers)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)()>
: unary_function<_T1*, _Res>
template<typename _Tp, bool = is_member_function_pointer<_Tp>::value>
struct _Reference_wrapper_base_memfun
: _Reference_wrapper_base<_Tp>
{ };
// - a pointer to member function type (binary, no qualifiers)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2)>
: binary_function<_T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, const)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() const>
: unary_function<const _T1*, _Res>
{ };
// - a pointer to member function type (binary, const)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const>
: binary_function<const _T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, volatile)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() volatile>
: unary_function<volatile _T1*, _Res>
{ };
// - a pointer to member function type (binary, volatile)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) volatile>
: binary_function<volatile _T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, const volatile)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() const volatile>
: unary_function<const volatile _T1*, _Res>
{ };
// - a pointer to member function type (binary, const volatile)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const volatile>
: binary_function<const volatile _T1*, _T2, _Res>
{ };
template<typename _MemFunPtr>
struct _Reference_wrapper_base_memfun<_MemFunPtr, true>
: _Mem_fn_traits<_MemFunPtr>::__maybe_type
{
using result_type = typename _Mem_fn_traits<_MemFunPtr>::__result_type;
};
/**
* @brief Primary class template for reference_wrapper.
@ -309,7 +287,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
*/
template<typename _Tp>
class reference_wrapper
: public _Reference_wrapper_base<typename remove_cv<_Tp>::type>
: public _Reference_wrapper_base_memfun<typename remove_cv<_Tp>::type>
{
_Tp* _M_data;

19
libstdc++-v3/include/bits/std_function.h
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@ -48,25 +48,6 @@ namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* Derives from @c unary_function or @c binary_function, or perhaps
* nothing, depending on the number of arguments provided. The
* primary template is the basis case, which derives nothing.
*/
template<typename _Res, typename... _ArgTypes>
struct _Maybe_unary_or_binary_function { };
/// Derives from @c unary_function, as appropriate.
template<typename _Res, typename _T1>
struct _Maybe_unary_or_binary_function<_Res, _T1>
: std::unary_function<_T1, _Res> { };
/// Derives from @c binary_function, as appropriate.
template<typename _Res, typename _T1, typename _T2>
struct _Maybe_unary_or_binary_function<_Res, _T1, _T2>
: std::binary_function<_T1, _T2, _Res> { };
/**
* @brief Exception class thrown when class template function's
* operator() is called with an empty target.

65
libstdc++-v3/include/std/functional
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@ -55,7 +55,8 @@
#include <type_traits>
#include <bits/functional_hash.h>
#include <bits/invoke.h>
#include <bits/std_function.h>
#include <bits/refwrap.h> // std::reference_wrapper and _Mem_fn_traits
#include <bits/std_function.h> // std::function
#if __cplusplus > 201402L
# include <unordered_map>
# include <vector>
@ -82,68 +83,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
#endif
template<typename... _Types>
struct _Pack : integral_constant<size_t, sizeof...(_Types)>
{ };
template<typename _From, typename _To, bool = _From::value == _To::value>
struct _AllConvertible : false_type
{ };
template<typename... _From, typename... _To>
struct _AllConvertible<_Pack<_From...>, _Pack<_To...>, true>
: __and_<is_convertible<_From, _To>...>
{ };
template<typename _Tp1, typename _Tp2>
using _NotSame = __not_<is_same<typename std::decay<_Tp1>::type,
typename std::decay<_Tp2>::type>>;
template<typename _Signature>
struct _Mem_fn_traits;
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Mem_fn_traits_base
{
using __result_type = _Res;
using __maybe_type
= _Maybe_unary_or_binary_function<_Res, _Class*, _ArgTypes...>;
using __arity = integral_constant<size_t, sizeof...(_ArgTypes)>;
};
#define _GLIBCXX_MEM_FN_TRAITS2(_CV, _REF, _LVAL, _RVAL) \
template<typename _Res, typename _Class, typename... _ArgTypes> \
struct _Mem_fn_traits<_Res (_Class::*)(_ArgTypes...) _CV _REF> \
: _Mem_fn_traits_base<_Res, _CV _Class, _ArgTypes...> \
{ \
using __vararg = false_type; \
}; \
template<typename _Res, typename _Class, typename... _ArgTypes> \
struct _Mem_fn_traits<_Res (_Class::*)(_ArgTypes... ...) _CV _REF> \
: _Mem_fn_traits_base<_Res, _CV _Class, _ArgTypes...> \
{ \
using __vararg = true_type; \
};
#define _GLIBCXX_MEM_FN_TRAITS(_REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2( , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(const , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(volatile , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(const volatile, _REF, _LVAL, _RVAL)
_GLIBCXX_MEM_FN_TRAITS( , true_type, true_type)
_GLIBCXX_MEM_FN_TRAITS(&, true_type, false_type)
_GLIBCXX_MEM_FN_TRAITS(&&, false_type, true_type)
#if __cplusplus > 201402L
_GLIBCXX_MEM_FN_TRAITS(noexcept, true_type, true_type)
_GLIBCXX_MEM_FN_TRAITS(& noexcept, true_type, false_type)
_GLIBCXX_MEM_FN_TRAITS(&& noexcept, false_type, true_type)
#endif
#undef _GLIBCXX_MEM_FN_TRAITS
#undef _GLIBCXX_MEM_FN_TRAITS2
template<typename _MemFunPtr,
bool __is_mem_fn = is_member_function_pointer<_MemFunPtr>::value>
class _Mem_fn_base

31
libstdc++-v3/testsuite/20_util/bind/83427.cc Normal file
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@ -0,0 +1,31 @@
// Copyright (C) 2017 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-options "-std=gnu++17" }
// { dg-do compile { target c++17 } }
#include <functional>
// PR libstdc++/83427
int f() noexcept { return 0; }
auto b = std::bind(f);
static_assert(std::is_same_v<decltype(b)::result_type, int>);
struct X { long f() const & noexcept { return 0L; } };
auto b2 = std::bind(&X::f, X{});
static_assert(std::is_same_v<decltype(b2)::result_type, long>);

8
libstdc++-v3/testsuite/20_util/bind/refqual.cc
View File

@ -22,8 +22,8 @@
struct X
{
int f() const& { return 0; }
int g(int i, ...)& { return i; }
int f() const& noexcept { return 0; }
int g(int i, ...)& noexcept { return i; }
};
void
@ -34,6 +34,10 @@ test01()
VERIFY( b() == 0 );
auto bb = std::bind(&X::g, &x, 1, 2);
VERIFY( bb() == 1 );
// Check for weak result types:
using T1 = decltype(b)::result_type;
using T2 = decltype(bb)::result_type;
}
int

39
libstdc++-v3/testsuite/20_util/reference_wrapper/83427.cc Normal file
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@ -0,0 +1,39 @@
// Copyright (C) 2017 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-options "-std=gnu++17" }
// { dg-do compile { target c++17 } }
#include <functional>
// PR libstdc++/83427
int f(short) noexcept { return 0; }
std::reference_wrapper<decltype(f)> r(f);
static_assert(std::is_same_v<decltype(r)::result_type, int>);
static_assert(std::is_same_v<decltype(r)::argument_type, short>);
auto* p = &f;
std::reference_wrapper<decltype(&f)> r2(p);
static_assert(std::is_same_v<decltype(r2)::result_type, int>);
static_assert(std::is_same_v<decltype(r2)::argument_type, short>);
struct X { long f() const & noexcept { return 0L; } };
auto m = &X::f;
std::reference_wrapper<decltype(m)> r3(m);
static_assert(std::is_same_v<decltype(r3)::result_type, long>);
static_assert(std::is_same_v<decltype(r3)::argument_type, const X*>);