{"id":2226651,"url":"http://patchwork.ozlabs.org/api/covers/2226651/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/cover/bmm.hhunqjrqt2.gcc.gcc-TEST.redi.37.1.0@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":"2026-04-22T17:58:45","name":"[v1,0/1] libstdc++: Add missing static_assert to std::expected::value()&&","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"},"mbox":"http://patchwork.ozlabs.org/project/gcc/cover/bmm.hhunqjrqt2.gcc.gcc-TEST.redi.37.1.0@forge-stage.sourceware.org/mbox/","series":[{"id":501058,"url":"http://patchwork.ozlabs.org/api/series/501058/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/list/?series=501058","date":"2026-04-22T17:58:46","name":"libstdc++: Add missing static_assert to std::expected::value()&&","version":1,"mbox":"http://patchwork.ozlabs.org/series/501058/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/covers/2226651/comments/","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; helo=vm01.sourceware.org;\n envelope-from=gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org;\n receiver=patchwork.ozlabs.org)","sourceware.org; dmarc=none (p=none dis=none)\n header.from=forge-stage.sourceware.org","sourceware.org;\n spf=pass smtp.mailfrom=forge-stage.sourceware.org","server2.sourceware.org;\n arc=none smtp.remote-ip=38.145.34.39"],"Received":["from vm01.sourceware.org (vm01.sourceware.org [38.145.34.32])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4g16V94srZz1yD5\n\tfor ; Thu, 23 Apr 2026 04:01:21 +1000 (AEST)","from vm01.sourceware.org (localhost [127.0.0.1])\n\tby sourceware.org (Postfix) with ESMTP id C6FB94BB5912\n\tfor ; Wed, 22 Apr 2026 18:01:19 +0000 (GMT)","from forge-stage.sourceware.org (vm08.sourceware.org [38.145.34.39])\n by sourceware.org (Postfix) with ESMTPS id D61A04BB58AC\n for ; Wed, 22 Apr 2026 17:59:37 +0000 (GMT)","from forge-stage.sourceware.org (localhost [IPv6:::1])\n (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n key-exchange x25519 server-signature ECDSA (prime256v1) server-digest SHA256)\n (No client certificate requested)\n by forge-stage.sourceware.org (Postfix) with ESMTPS id A7CED42BFE\n for ; Wed, 22 Apr 2026 17:59:37 +0000 (UTC)"],"DKIM-Filter":["OpenDKIM Filter v2.11.0 sourceware.org C6FB94BB5912","OpenDKIM Filter v2.11.0 sourceware.org D61A04BB58AC"],"DMARC-Filter":"OpenDMARC Filter v1.4.2 sourceware.org D61A04BB58AC","ARC-Filter":"OpenARC Filter v1.0.0 sourceware.org D61A04BB58AC","ARC-Seal":"i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1776880777; cv=none;\n b=CyrgwcyaRw7ngJ9kFRuoTh+bDGinvPzUxe4hrFa2Wj5YIEQxUWnIvHggCYT7JawrX70cHTjFzKhNjv0i/9aQSmk7CIFVmA9RozCz1rhdmnroWXSAylffGPrB8uw1LkYl+nI49lYQxSs5IrQ1SHwmK58TZPgoFjweIX5DYJ74lO0=","ARC-Message-Signature":"i=1; a=rsa-sha256; d=sourceware.org; s=key;\n t=1776880777; c=relaxed/simple;\n bh=wqtGdth+v8AIkJW72Ds9oJ5m4hq+CPlp83QMEbyYuRs=;\n h=From:Date:Subject:To:Message-ID;\n b=O4M9KmK+T+sXzxDhCkA1j85n+WiM+QfpTIcqX6wuqyOKPltEwSonPzsZkjqMq/63+5z1CQPDFbdvVRPGHy6KSi5XeKr60H92BO5AF4aqQQWj8sbe8z0DGSPFAd92U32V9kOW4Ka5XrawNmHQIl/fO5vMuuSFKDSctyLCe0BDpnM=","ARC-Authentication-Results":"i=1; server2.sourceware.org","From":"Jonathan Wakely via Sourceware Forge\n ","Date":"Wed, 22 Apr 2026 17:58:45 +0000","Subject":"[PATCH v1 0/1] libstdc++: Add missing static_assert to\n std::expected::value()&&","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/37","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":"Hi gcc-patches mailing list,\nJonathan Wakely via Sourceware Forge has requested that the following forgejo pull request\nbe published on the mailing list.\n\nCreated on: 2025-03-06 20:14:21+00:00\nLatest update: 2025-08-13 03:38:33+00:00\nChanges: 2 changed files, 70 additions, 0 deletions\nHead revision: redi/gcc ref expected-void-value commit 62b2ee5099bb3aa807112e827ea224427071a2b2\nBase revision: gcc/gcc-TEST ref trunk commit be0942afb3a7080b7b0420a5369bdcf3dcc74b52 r15-7872-gbe0942afb3a708\nMerge base: be0942afb3a7080b7b0420a5369bdcf3dcc74b52\nFull diff url: https://forge.sourceware.org/gcc/gcc-TEST/pulls/37.diff\nDiscussion: https://forge.sourceware.org/gcc/gcc-TEST/pulls/37\nRequested Reviewers:\n\nThe [r15-2326-gea435261ad58ea](https://gcc.gnu.org/r15-2326-gea435261ad58ea) change missed a `static_assert` for\n`is_move_constructible_v` in `expected::value()&&`. When\nexceptions are enabled, the program is ill-formed if the error type is\nnot move constructible, because we can't construct the\n`std::bad_expected_access`. But when using `-fno-exceptions`, we never\nconstruct an exception, so don't need to copy/move the error value. So\nthat the same code compiles with/without exceptions enabled, we should\nenforce the requirement explicitly.\n\nAdd the `static_assert`, and a test that verifies the Mandates:\nconditions added by LWG [3843](https://wg21.link/lwg3843) and [3490](https://wg21.link/lwg3490) are enforced even with\n`-fno-exceptions`.\n\n```\nlibstdc++-v3/ChangeLog:\n\n\t* include/std/expected (expected::value()&&):\n\tAdd missing static_assert for LWG 3940.\n\t* testsuite/20_util/expected/lwg3843.cc: New test.\n```\n\n\nChanged files:\n- A: libstdc++-v3/testsuite/20_util/expected/lwg3843.cc\n- M: libstdc++-v3/include/std/expected\n\n\nJonathan Wakely (1):\n libstdc++: Add missing static_assert to\n std::expected::value()&&\n\n libstdc++-v3/include/std/expected | 1 +\n .../testsuite/20_util/expected/lwg3843.cc | 69 +++++++++++++++++++\n 2 files changed, 70 insertions(+)\n create mode 100644 libstdc++-v3/testsuite/20_util/expected/lwg3843.cc"}