From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from rock.gnat.com (rock.gnat.com [IPv6:2620:20:4000:0:a9e:1ff:fe9b:1d1]) by sourceware.org (Postfix) with ESMTPS id 379033858D33 for ; Wed, 28 Dec 2022 12:33:00 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 379033858D33 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=adacore.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=adacore.com Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id 07903116316; Wed, 28 Dec 2022 07:33:00 -0500 (EST) 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 KEJ2LGTJ+gFU; Wed, 28 Dec 2022 07:32:59 -0500 (EST) 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 C8688116312; Wed, 28 Dec 2022 07:32:59 -0500 (EST) Received: from livre (livre.home [172.31.160.2]) by free.home (8.15.2/8.15.2) with ESMTPS id 2BSCWq86743588 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Wed, 28 Dec 2022 09:32:53 -0300 From: Alexandre Oliva To: David Malcolm Cc: gcc-patches@gcc.gnu.org Subject: [15/17] prevent hash set/map insertion of deleted entries Organization: Free thinker, does not speak for AdaCore References: <613b4501636146942775f23cfa8035f9eb7b84d3.camel@redhat.com> Errors-To: aoliva@lxoliva.fsfla.org Date: Wed, 28 Dec 2022 09:32:52 -0300 In-Reply-To: <613b4501636146942775f23cfa8035f9eb7b84d3.camel@redhat.com> (David Malcolm's message of "Tue, 27 Dec 2022 12:53:18 -0500") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain 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 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: On Dec 27, 2022, David Malcolm wrote: > Would it make sense to also add assertions that such entries aren't > Traits::is_deleted? (both for hash_map and hash_set) Yeah, I guess so. I've come up with something for hash-table proper too, coming up in 17/17. Just like the recently-added checks for empty entries, add checks for deleted entries as well. This didn't catch any problems, but it might prevent future accidents. Suggested by David Malcolm. Regstrapped on x86_64-linux-gnu. Ok to install? for gcc/ChangeLog * hash-map.h (put, get_or_insert): Check that added entry doesn't look deleted either. & hash-set.h (add): Likewise. --- gcc/hash-map.h | 8 +++++--- gcc/hash-set.h | 3 ++- 2 files changed, 7 insertions(+), 4 deletions(-) diff --git a/gcc/hash-map.h b/gcc/hash-map.h index 63fa21cf37c5b..e6ca9cf5e6429 100644 --- a/gcc/hash-map.h +++ b/gcc/hash-map.h @@ -173,8 +173,9 @@ public: if (ins) { e->m_key = k; - new ((void *) &e->m_value) Value (v); - gcc_checking_assert (!Traits::is_empty (*e)); + new ((void *)&e->m_value) Value (v); + gcc_checking_assert (!Traits::is_empty (*e) + && !Traits::is_deleted (*e)); } else e->m_value = v; @@ -204,7 +205,8 @@ public: { e->m_key = k; new ((void *)&e->m_value) Value (); - gcc_checking_assert (!Traits::is_empty (*e)); + gcc_checking_assert (!Traits::is_empty (*e) + && !Traits::is_deleted (*e)); } if (existed != NULL) diff --git a/gcc/hash-set.h b/gcc/hash-set.h index a98121a060eed..08e1851d5118d 100644 --- a/gcc/hash-set.h +++ b/gcc/hash-set.h @@ -61,7 +61,8 @@ public: { new (e) Key (k); // Catch attempts to insert e.g. a NULL pointer. - gcc_checking_assert (!Traits::is_empty (*e)); + gcc_checking_assert (!Traits::is_empty (*e) + && !Traits::is_deleted (*e)); } return existed; -- Alexandre Oliva, happy hacker https://FSFLA.org/blogs/lxo/ Free Software Activist GNU Toolchain Engineer Disinformation flourishes because many people care deeply about injustice but very few check the facts. Ask me about