From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id EDA623858D28; Sat, 24 Sep 2022 00:07:22 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org EDA623858D28 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1663978042; bh=fKtgttSa2AAjQxvT2COjDoEED9EkNL2Xg1h41xeQVdU=; h=From:To:Subject:Date:From; b=R4NjoKL584bgeQKs1LGY1XfME06sa5lV8zGPBwJAak6jDxCK/KzBmNFLNuXZAgung rtab0iT4KRy8FSvA19Wo7fEBvvoxg6W3WLeeQ00K5bXl1C+1OXQK/fLXreUmzXec1k 0xElyQjZQo0vqD00aGjZyZ2O9MSnybHnDPSmFBEs= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jonathan Wakely To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc r13-2825] libstdc++: Fix std::is_nothrow_invocable_r for uncopyable prvalues [PR91456] X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/master X-Git-Oldrev: d88319de4165cd58764f0611df03179d6ce4d160 X-Git-Newrev: 71c828f84572d933979468baf2cf744180258ee4 Message-Id: <20220924000722.EDA623858D28@sourceware.org> Date: Sat, 24 Sep 2022 00:07:22 +0000 (GMT) List-Id: https://gcc.gnu.org/g:71c828f84572d933979468baf2cf744180258ee4 commit r13-2825-g71c828f84572d933979468baf2cf744180258ee4 Author: Jonathan Wakely Date: Fri Sep 23 13:28:37 2022 +0100 libstdc++: Fix std::is_nothrow_invocable_r for uncopyable prvalues [PR91456] This is the last missing piece of PR 91456. This also removes the only use of the C++11 version of std::is_nothrow_invocable, which was just renamed to __is_nothrow_invocable_lib. We can remove that now. libstdc++-v3/ChangeLog: PR libstdc++/91456 * include/std/type_traits (__is_nothrow_invocable_lib): Remove. (__is_invocable_impl::__nothrow_type): New member type which checks if the conversion can throw. (__is_nt_invocable_impl): Replace class template with alias template to __is_nt_invocable_impl::__nothrow_type. * testsuite/20_util/is_nothrow_invocable/91456.cc: New test. * testsuite/20_util/is_nothrow_convertible/value.cc: Remove macro used by value_ext.cc test. * testsuite/20_util/is_nothrow_convertible/value_ext.cc: Remove test for non-standard __is_nothrow_invocable_lib trait. Diff: --- libstdc++-v3/include/std/type_traits | 45 +++++++++++----------- .../20_util/is_nothrow_convertible/value.cc | 2 - .../value_ext.cc => is_nothrow_invocable/91456.cc} | 19 ++++++--- 3 files changed, 36 insertions(+), 30 deletions(-) diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index 1797b9e97f7..7c635313a95 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -1451,12 +1451,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION }; #pragma GCC diagnostic pop - // is_nothrow_convertible for C++11 - template - struct __is_nothrow_convertible_lib - : public __is_nt_convertible_helper<_From, _To>::type - { }; - #if __cplusplus > 201703L #define __cpp_lib_is_nothrow_convertible 201806L /// is_nothrow_convertible @@ -2825,7 +2819,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // The primary template is used for invalid INVOKE expressions. template::value, typename = void> - struct __is_invocable_impl : false_type { }; + struct __is_invocable_impl + : false_type + { + using __nothrow_type = false_type; // For is_nothrow_invocable_r + }; // Used for valid INVOKE and INVOKE expressions. template @@ -2833,7 +2831,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION /* is_void<_Ret> = */ true, __void_t> : true_type - { }; + { + using __nothrow_type = true_type; // For is_nothrow_invocable_r + }; #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wctor-dtor-privacy" @@ -2845,23 +2845,30 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { private: // The type of the INVOKE expression. - // Unlike declval, this doesn't add_rvalue_reference. - static typename _Result::type _S_get(); + // Unlike declval, this doesn't add_rvalue_reference, so it respects + // guaranteed copy elision. + static typename _Result::type _S_get() noexcept; template - static void _S_conv(_Tp); + static void _S_conv(_Tp) noexcept; // This overload is viable if INVOKE(f, args...) can convert to _Tp. - template(_S_get()))> - static true_type + template(_S_get())), + bool _Noex = noexcept(_S_conv<_Tp>(_S_get()))> + static __bool_constant<_Check_Noex ? _Noex : true> _S_test(int); - template + template static false_type _S_test(...); public: + // For is_invocable_r using type = decltype(_S_test<_Ret>(1)); + + // For is_nothrow_invocable_r + using __nothrow_type = decltype(_S_test<_Ret, true>(1)); }; #pragma GCC diagnostic pop @@ -2992,15 +2999,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION }; /// @cond undocumented - template - struct __is_nt_invocable_impl : false_type { }; - template - struct __is_nt_invocable_impl<_Result, _Ret, - __void_t> - : __or_, - __is_nothrow_convertible_lib>::type - { }; + using __is_nt_invocable_impl + = typename __is_invocable_impl<_Result, _Ret>::__nothrow_type; /// @endcond /// std::is_nothrow_invocable_r diff --git a/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value.cc b/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value.cc index e9aded73624..a2686285052 100644 --- a/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value.cc +++ b/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value.cc @@ -21,9 +21,7 @@ #include #include -#ifndef IS_NT_CONVERTIBLE_DEFINED using std::is_nothrow_convertible; -#endif void test01() { diff --git a/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value_ext.cc b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/91456.cc similarity index 59% rename from libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value_ext.cc rename to libstdc++-v3/testsuite/20_util/is_nothrow_invocable/91456.cc index d736d2ca260..abbbd1aade4 100644 --- a/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value_ext.cc +++ b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/91456.cc @@ -15,14 +15,21 @@ // with this library; see the file COPYING3. If not see // . -// { dg-do compile { target c++11 } } +// { dg-do compile { target c++17 } } + +// PR 91456 +// std::function and std::is_invocable_r do not understand guaranteed elision #include -// Test the non-standard __is_nothrow_convertible_lib trait +#include -template - using is_nothrow_convertible = std::__is_nothrow_convertible_lib; +struct Immovable { + Immovable() = default; + Immovable(const Immovable&) = delete; + Immovable& operator=(const Immovable&) = delete; +}; -#define IS_NT_CONVERTIBLE_DEFINED -#include "value.cc" +static_assert(std::is_nothrow_invocable_r_v); +static_assert(std::is_nothrow_invocable_r_v); +static_assert(std::is_nothrow_invocable_r_v);