From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id 3C1F83858C33 for ; Fri, 13 Jan 2023 22:51:39 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 3C1F83858C33 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673650298; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ephf2ROqv+LfSs8dRoqWCCtJ/KDMkjTdaL+U6mZHa2s=; b=DnbRtjE8475QeTgZCK0kO1bwy8o/v0SjXloTxcKNjl3xRiV4cicT+mMySx3NYTjHabg/YX gLLxNz9c1gVURHqPFSa4sjGr0P6mI5PUqlN0D+v9ID052kKGNAYf+QlX1I3ViZDIwK+bsj jRIyeoPAtfiX0AuR2k10WYIweBlX+oY= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-624-IX05vBm-PuuV0aRJaolJKg-1; Fri, 13 Jan 2023 17:51:35 -0500 X-MC-Unique: IX05vBm-PuuV0aRJaolJKg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2725580D0ED; Fri, 13 Jan 2023 22:51:35 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.39.192.223]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CB0431121314; Fri, 13 Jan 2023 22:51:34 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.17.1/8.17.1) with ESMTPS id 30DMpUJI1699113 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Fri, 13 Jan 2023 23:51:31 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.17.1/8.17.1/Submit) id 30DMpTvQ1699071; Fri, 13 Jan 2023 23:51:29 +0100 Date: Fri, 13 Jan 2023 23:51:29 +0100 From: Jakub Jelinek To: Richard Earnshaw Cc: "Richard Earnshaw (lists)" , Srinath Parvathaneni , gcc Patches , Kyrylo Tkachov , Richard Sandiford Subject: Re: [GCC][PATCH 13/15, v5] arm: Add support for dwarf debug directives and pseudo hard-register for PAC feature. Message-ID: Reply-To: Jakub Jelinek References: <2b3432d1-587e-4c2e-4297-327ffbe6ad1d@arm.com> <87fd94ab-f910-3164-6595-54ac8e7e1314@foss.arm.com> MIME-Version: 1.0 In-Reply-To: <87fd94ab-f910-3164-6595-54ac8e7e1314@foss.arm.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-3.5 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,KAM_SHORT,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,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 Fri, Jan 13, 2023 at 10:39:59PM +0000, Richard Earnshaw wrote: > > > It is.  The new unwinder fortunately doesn't suffer from this (at least I > > > think it doesn't), but in older gccs the unwinder could be split > > > across different > > > objects, having e.g. parts of the unwinder in one shared library and > > > another > > > part in another one, each built by different GCC version. > > > > > > Guess targets which weren't supported in GCC 2.x are ok, while > > > __frame_state_for is in libgcc, nothing calls it, so while such changes > > > change the ABI, nothing likely cares. > > > But for older targets it is a problem. > > > > > > And it is hard to catch this in the testsuite, one would either need to > > > hardcode the count for each target in the test, or test with mixing > > > GCC 2.x > > > compiled code with current trunk. > > > > > > Before the introduction of libgcc_eh.a etc., parts of the unwinder > > > was e.g. > > > exported from glibc. > > > See e.g. > > > https://gcc.gnu.org/legacy-ml/gcc-patches/2001-07/threads.html#00472 > > > > > > for some details. > > > > So: > > 1) GCC-2.* didn't support the EABI, which is all we support these days. > > 2) the Arm port updated FIRST_PSEUDO_REGISTER in 2019 in r10-4441 > > (16155ccf588a403c033ccd7743329671bcfb27d5) and I didn't see any fallout > > from that. > In fact it's been changed in > > 16155ccf588a > cf16f980e527 > 0be8bd1a1c89 > f1adb0a9f4d7 > 9b66ebb1460d > 5a9335ef017c > > All since 2003 (ie since gcc-3.0 was released). You're right, t-bpabi uses unwind-arm.c rather than unwind-dw2.c. Sorry for the false alarm. Jakub