{"id":2226664,"url":"http://patchwork.ozlabs.org/api/patches/2226664/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/patch/bmm.hhunv1vldi.gcc.gcc-TEST.redi.40.1.1@forge-stage.sourceware.org/","project":{"id":17,"url":"http://patchwork.ozlabs.org/api/projects/17/?format=json","name":"GNU Compiler Collection","link_name":"gcc","list_id":"gcc-patches.gcc.gnu.org","list_email":"gcc-patches@gcc.gnu.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"","list_archive_url":null,"date":"2026-04-22T18:03:18","name":"[v1,1/1] libstdc++: Add poison pill for chrono::from_stream","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"fdedd6ef552a234922ee9975d6b54a5830ee1734","submitter":{"id":93210,"url":"http://patchwork.ozlabs.org/api/people/93210/?format=json","name":"Jonathan Wakely via Sourceware Forge","email":"forge-bot+redi@forge-stage.sourceware.org"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/gcc/patch/bmm.hhunv1vldi.gcc.gcc-TEST.redi.40.1.1@forge-stage.sourceware.org/mbox/","series":[{"id":501063,"url":"http://patchwork.ozlabs.org/api/series/501063/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/list/?series=501063","date":"2026-04-22T18:03:17","name":"libstdc++: Add poison pill for chrono::from_stream","version":1,"mbox":"http://patchwork.ozlabs.org/series/501063/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2226664/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2226664/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":["incoming@patchwork.ozlabs.org","gcc-patches@gcc.gnu.org"],"Delivered-To":["patchwork-incoming@legolas.ozlabs.org","gcc-patches@gcc.gnu.org"],"Authentication-Results":["legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org\n (client-ip=38.145.34.32; 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server2.sourceware.org","From":"Jonathan Wakely via Sourceware Forge\n ","Date":"Wed, 22 Apr 2026 18:03:18 +0000","Subject":"[PATCH v1 1/1] libstdc++: Add poison pill for chrono::from_stream","To":"gcc-patches mailing list ","Message-ID":"\n ","X-Mailer":"batrachomyomachia","X-Pull-Request-Organization":"gcc","X-Pull-Request-Repository":"gcc-TEST","X-Pull-Request":"https://forge.sourceware.org/gcc/gcc-TEST/pulls/40","References":"\n ","In-Reply-To":"\n ","X-Patch-URL":"\n https://forge.sourceware.org/redi/gcc/commit/5b8e44a0eff642731e54648f4ba3ff6afec9b0c1","X-BeenThere":"gcc-patches@gcc.gnu.org","X-Mailman-Version":"2.1.30","Precedence":"list","List-Id":"Gcc-patches mailing list ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Reply-To":"gcc-patches mailing list , redi@gcc.gnu.org","Errors-To":"gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org"},"content":"From: Jonathan Wakely \n\nLWG 3956 (approved in Hagenberg, February 2025) decided that from_stream\nshould be found *only* by ADL, not ordinary unqualified lookup. Add a\npoison pill overload to chrono::__detail where the __parsable and\noperator>>(basic_istream&, _Parser) are defined. This ensures that when\nthey use from_stream unqualified ordinary lookup finds the poison pill,\nwhich is deleted, so a usable overload resolution result can only be\nfound by ADL.\n\nWe already have the std/time/parse/parse.cc test checking that ADL\nworks, so this doesn't add a new test.\n\nlibstdc++-v3/ChangeLog:\n\n\t* include/bits/chrono_io.h (chrono::__detail::from_stream): Add\n\tdeleted function as poison pill for unqualified lookup.\n---\n libstdc++-v3/include/bits/chrono_io.h | 4 ++++\n 1 file changed, 4 insertions(+)","diff":"diff --git a/libstdc++-v3/include/bits/chrono_io.h b/libstdc++-v3/include/bits/chrono_io.h\nindex 8c026586d4c9..c16b555df290 100644\n--- a/libstdc++-v3/include/bits/chrono_io.h\n+++ b/libstdc++-v3/include/bits/chrono_io.h\n@@ -3115,6 +3115,10 @@ namespace __detail\n \n namespace __detail\n {\n+ // _GLIBCXX_RESOLVE_LIB_DEFECTS\n+ // 3956. chrono::parse uses from_stream as a customization point\n+ void from_stream() = delete;\n+\n template,\n \t typename... _OptArgs>\n","prefixes":["v1","1/1"]}