From patchwork Tue Jun 21 06:03:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Oliva X-Patchwork-Id: 1645853 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=gcc.gnu.org header.i=@gcc.gnu.org header.a=rsa-sha256 header.s=default header.b=H7BoY8KI; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org (client-ip=8.43.85.97; helo=sourceware.org; envelope-from=gcc-patches-bounces+incoming=patchwork.ozlabs.org@gcc.gnu.org; receiver=) Received: from sourceware.org (ip-8-43-85-97.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4LRww55Nd3z9sGT for ; Tue, 21 Jun 2022 16:04:52 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id BFFDE387085B for ; Tue, 21 Jun 2022 06:04:49 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org BFFDE387085B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1655791489; bh=Kt5RBVXlaqr5f5zkGTnZt9Dxh6kQ0/eu1XCDBJ5QPaQ=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=H7BoY8KIs24ROgvKnjKlUzI4TTBy3MCzAmvnrQcOJvp7OXXcyOWazTV7DfNsEYQfH 6Uv1QYSWF8tBwBntcR0xzWAkdz/YPz79U6xGac4Yc6Os1/A1Zyy/OOPLZH0DRTVkTg 8C8ttl83CS+46+B9c6SR794bvpSHNzzf7XD/nRHU= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from rock.gnat.com (rock.gnat.com [IPv6:2620:20:4000:0:a9e:1ff:fe9b:1d1]) by sourceware.org (Postfix) with ESMTPS id 409DD3841459; Tue, 21 Jun 2022 06:03:49 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 409DD3841459 Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id 05A251160D8; Tue, 21 Jun 2022 02:03:49 -0400 (EDT) X-Virus-Scanned: Debian amavisd-new at gnat.com Received: from rock.gnat.com ([127.0.0.1]) by localhost (rock.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id iPgkBxiXPjHv; Tue, 21 Jun 2022 02:03:48 -0400 (EDT) Received: from free.home (tron.gnat.com [IPv6:2620:20:4000:0:46a8:42ff:fe0e:e294]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by rock.gnat.com (Postfix) with ESMTPS id C31801160B7; Tue, 21 Jun 2022 02:03:48 -0400 (EDT) Received: from livre (livre.home [172.31.160.2]) by free.home (8.15.2/8.15.2) with ESMTPS id 25L63fVB693603 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 21 Jun 2022 03:03:41 -0300 To: gcc-patches@gcc.gnu.org, libstdc++@gcc.gnu.org Subject: [PATCH] libstdc++: eh_globals: gthreads: reset _S_init before deleting key Organization: Free thinker, does not speak for AdaCore Date: Tue, 21 Jun 2022 03:03:41 -0300 Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 X-Spam-Status: No, score=-12.3 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Alexandre Oliva via Gcc-patches From: Alexandre Oliva Reply-To: Alexandre Oliva Errors-To: gcc-patches-bounces+incoming=patchwork.ozlabs.org@gcc.gnu.org Sender: "Gcc-patches" Clear __eh_globals_init's _S_init in the dtor before deleting the gthread key. This ensures that, in case any code involved in deleting the key interacts with eh_globals, the key that is being deleted won't be used, and the non-thread-specific eh_globals fallback will. Regstrapped on x86_64-linux-gnu, also tested with a cross to aarch64-rtems6. Ok to install? PS: This is a fix for a theoretical issue, that came to mind while I independently investigated the problem that I later found to be PR105880. for libstdc++-v3/ChangeLog * libsupc++/eh_globals.cc [!_GLIBCXX_HAVE_TLS] (__eh_globals_init::~__eh_globals_init): Clear _S_init first. --- libstdc++-v3/libsupc++/eh_globals.cc | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/libstdc++-v3/libsupc++/eh_globals.cc b/libstdc++-v3/libsupc++/eh_globals.cc index 768425c0f407a..0aadb692a9625 100644 --- a/libstdc++-v3/libsupc++/eh_globals.cc +++ b/libstdc++-v3/libsupc++/eh_globals.cc @@ -119,8 +119,13 @@ struct __eh_globals_init ~__eh_globals_init() { if (_S_init) - __gthread_key_delete(_M_key); - _S_init = false; + { + /* Set it before the call, so that, should + __gthread_key_delete throw an exception, it won't rely on + the key being deleted. */ + _S_init = false; + __gthread_key_delete(_M_key); + } } __eh_globals_init(const __eh_globals_init&) = delete;