public inbox for libstdc++-cvs@sourceware.org help / color / mirror / Atom feed
From: Peter Bergner <bergner@gcc.gnu.org> To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc(refs/vendors/ibm/heads/gcc-10-branch)] libstdc++: Fix ambiguous comparisons in __gnu_debug::bitset [PR 96303] Date: Wed, 19 Aug 2020 13:58:23 +0000 (GMT) [thread overview] Message-ID: <20200819135823.BDD3D386F022@sourceware.org> (raw) https://gcc.gnu.org/g:7e26e4fbd4ee618dd991c6bbf3c5403aa90d2192 commit 7e26e4fbd4ee618dd991c6bbf3c5403aa90d2192 Author: Jonathan Wakely <jwakely@redhat.com> Date: Fri Aug 7 20:29:11 2020 +0100 libstdc++: Fix ambiguous comparisons in __gnu_debug::bitset [PR 96303] With -pedantic the debug mode bitset has an ambiguous equality comparison operator, because it tries to compare the non-debug base to the debug object. The base object can be converted to another debug bitset, making the same operator== a candidate again. The fix is to do the comparison on both base objects, so the operator for the derived type isn't a candidate. For the inequality operator the same change should be done, but that operator can be removed entirely for C++20 because it can be synthesized by the compiler. I don't think either equality or inequality operators are really needed, because the public _GLIBCXX_STD_C::bitset base class cam always be compared using its own comparison operators. I'm not changing that here though. libstdc++-v3/ChangeLog: PR libstdc++/96303 * include/debug/bitset (bitset::operator==): Call _M_base() on right operand. (bitset::operator!=): Likewise, but don't define it at all when default comparisons are supported by the compiler. * testsuite/23_containers/bitset/operations/96303.cc: New test. (cherry picked from commit de1e3b8795e507c3cfa5b62984272628ca62a9bd) Diff: --- libstdc++-v3/include/debug/bitset | 6 +++-- .../23_containers/bitset/operations/96303.cc | 31 ++++++++++++++++++++++ 2 files changed, 35 insertions(+), 2 deletions(-) diff --git a/libstdc++-v3/include/debug/bitset b/libstdc++-v3/include/debug/bitset index fb498012605..1b8dc6d422c 100644 --- a/libstdc++-v3/include/debug/bitset +++ b/libstdc++-v3/include/debug/bitset @@ -353,11 +353,13 @@ namespace __debug bool operator==(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT - { return _M_base() == __rhs; } + { return _M_base() == __rhs._M_base(); } +#if __cpp_impl_three_way_comparison < 201907L bool operator!=(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT - { return _M_base() != __rhs; } + { return _M_base() != __rhs._M_base(); } +#endif using _Base::test; using _Base::all; diff --git a/libstdc++-v3/testsuite/23_containers/bitset/operations/96303.cc b/libstdc++-v3/testsuite/23_containers/bitset/operations/96303.cc new file mode 100644 index 00000000000..ab31e3c47d5 --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/bitset/operations/96303.cc @@ -0,0 +1,31 @@ +// Copyright (C) 2020 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++2a -pedantic" } +// { dg-do compile { target c++2a } } + +#include <debug/bitset> + +bool +test01() +{ + __gnu_debug::bitset<1> b; + // PR libstdc++/96303 + bool eq = b == b; + bool ne = b != b; + return eq && !ne; +}
reply other threads:[~2020-08-19 13:58 UTC|newest] Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20200819135823.BDD3D386F022@sourceware.org \ --to=bergner@gcc.gnu.org \ --cc=gcc-cvs@gcc.gnu.org \ --cc=libstdc++-cvs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).