From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id 56AB83857439; Tue, 12 Oct 2021 16:27:55 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 56AB83857439 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 r10-10181] libstdc++: Fix std::match_results::end() for failed matches [PR102667] X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/releases/gcc-10 X-Git-Oldrev: bde91c72cb2cc47cd169d2a59470177dd7a1d2b9 X-Git-Newrev: be3fbe792444bc750a8a1b37481bac9a84528949 Message-Id: <20211012162755.56AB83857439@sourceware.org> Date: Tue, 12 Oct 2021 16:27:55 +0000 (GMT) X-BeenThere: libstdc++-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Oct 2021 16:27:55 -0000 https://gcc.gnu.org/g:be3fbe792444bc750a8a1b37481bac9a84528949 commit r10-10181-gbe3fbe792444bc750a8a1b37481bac9a84528949 Author: Jonathan Wakely Date: Mon Oct 11 09:07:15 2021 +0100 libstdc++: Fix std::match_results::end() for failed matches [PR102667] The end() function needs to consider whether the underlying vector is empty, not whether the match_results object is empty. That's because the underlying vector will always contain at least three elements for a match_results object that is "ready". It contains three extra elements which are stored in the vector but are not considered part of sequence, and so should not be part of the [begin(),end()) range. libstdc++-v3/ChangeLog: PR libstdc++/102667 * include/bits/regex.h (match_result::empty()): Optimize by calling the base function directly. (match_results::end()): Check _Base_type::empty() not empty(). * testsuite/28_regex/match_results/102667.C: New test. (cherry picked from commit 84088dc4bb6a546c896a068dc201463493babf43) Diff: --- libstdc++-v3/include/bits/regex.h | 4 +-- .../testsuite/28_regex/match_results/102667.C | 39 ++++++++++++++++++++++ 2 files changed, 41 insertions(+), 2 deletions(-) diff --git a/libstdc++-v3/include/bits/regex.h b/libstdc++-v3/include/bits/regex.h index aa442e17656..ab09dc76c8a 100644 --- a/libstdc++-v3/include/bits/regex.h +++ b/libstdc++-v3/include/bits/regex.h @@ -1802,7 +1802,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 */ _GLIBCXX_NODISCARD bool empty() const noexcept - { return size() == 0; } + { return _Base_type::size() <= 3; } ///@} @@ -1920,7 +1920,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 */ const_iterator end() const noexcept - { return _Base_type::end() - (empty() ? 0 : 3); } + { return _Base_type::end() - (_Base_type::empty() ? 0 : 3); } /** * @brief Gets an iterator to one-past-the-end of the collection. diff --git a/libstdc++-v3/testsuite/28_regex/match_results/102667.C b/libstdc++-v3/testsuite/28_regex/match_results/102667.C new file mode 100644 index 00000000000..9e38c9edaa4 --- /dev/null +++ b/libstdc++-v3/testsuite/28_regex/match_results/102667.C @@ -0,0 +1,39 @@ +// { dg-do run { target c++11 } } + +#include +#include + +void +test01() +{ + std::cmatch sm; + VERIFY( sm.empty() ); + VERIFY( sm.size() == 0 ); + VERIFY( sm.begin() == sm.end() ); // PR libstdc++/83600 + + bool matched = std::regex_match("a", sm, std::regex("b")); + VERIFY( ! matched ); + VERIFY( sm.ready() ); + VERIFY( sm.empty() ); + VERIFY( sm.size() == 0 ); + VERIFY( sm.begin() == sm.end() ); // PR libstdc++/102667 + + matched = std::regex_match("a", sm, std::regex("a")); + VERIFY( matched ); + VERIFY( sm.ready() ); + VERIFY( ! sm.empty() ); + VERIFY( sm.size() == 1 ); + VERIFY( (sm.end() - sm.begin()) == 1 ); + + matched = std::regex_search("abcd", sm, std::regex("(b)(c)")); + VERIFY( matched ); + VERIFY( sm.ready() ); + VERIFY( ! sm.empty() ); + VERIFY( sm.size() == 3 ); + VERIFY( (sm.end() - sm.begin()) == 3 ); +} + +int main() +{ + test01(); +}