From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2001:67c:2178:6::1c]) by sourceware.org (Postfix) with ESMTPS id D7186385842B for ; Wed, 2 Aug 2023 18:46:38 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org D7186385842B Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=suse.de Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 01EEE21A01; Wed, 2 Aug 2023 18:46:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1691001998; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=6gczDSF6hdb71jgU5mkxIwKCbNBu1s2Ed5xlrWBRIJk=; b=mPweqhzrRp/iWStnCETp2glHNHb+roSqhL3qH7gSjlDo0QynIYvYiHvzbjZ63QaotgVmKw d7a5OkJizMx+aBqJt8VDaFlvZEoO+KSP/0Bpf94bVa1/wZ5EUNjIz0RmCt2SKhoFErTiWk rzeWOiNIWPROJaSmDtIkSKKRv1yrdHc= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1691001998; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=6gczDSF6hdb71jgU5mkxIwKCbNBu1s2Ed5xlrWBRIJk=; b=sLDhVX5mN0M6E6ZcaSbBwHlwt9wYeMXtVUEHtiEy7m2GEphxNiAuIlhmeezGQde+ELaqSm bLQjvNlNgZQyGyDA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id D6C1213909; Wed, 2 Aug 2023 18:46:37 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id KtJfM42kymRiCgAAMHmgww (envelope-from ); Wed, 02 Aug 2023 18:46:37 +0000 Content-Type: multipart/mixed; boundary="------------mKEKSbaublwLtEVT6a38qbMz" Message-ID: <8b34476a-aad0-589c-aa28-4465e5133acb@suse.de> Date: Wed, 2 Aug 2023 20:46:19 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/2] [gdb] Initialize main_thread_id earlier Content-Language: en-US To: Tom Tromey , Tom de Vries via Gdb-patches References: <20230728105945.13909-1-tdevries@suse.de> <20230728105945.13909-2-tdevries@suse.de> <877cqki3m0.fsf@tromey.com> <874jlhfkoi.fsf@tromey.com> From: Tom de Vries In-Reply-To: <874jlhfkoi.fsf@tromey.com> X-Spam-Status: No, score=-11.9 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,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 List-Id: This is a multi-part message in MIME format. --------------mKEKSbaublwLtEVT6a38qbMz Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 8/2/23 18:55, Tom Tromey wrote: >>>>>> "Tom" == Tom de Vries via Gdb-patches writes: > >>> I wonder if it's enough to have: >>> static std::thread::id main_thread_id = std::this_thread::get_id (); > > Tom> In principle it's enough but it does expose us to the "Static > Tom> Initialization Order Fiasco" [1], so I prefer this solution. > > If we think it's safe enough to initialize it on first use, just moving > the definition into is_main_thread is enough to avoid this problem. > Done. > Now, in theory it is possible for gdb to start a thread very early and > then have that thread call is_main_thread, setting the global > incorrectly. If we care about that then we need an explicit call to set > it early during startup. Yes, Pedro had the same remark, that was already fixed in the previous version. Any further comments? 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