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 [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id B0AA03848426 for ; Tue, 25 May 2021 07:40:39 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org B0AA03848426 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-25-xSqx932FML6K_PkPDGbfjA-1; Tue, 25 May 2021 03:40:37 -0400 X-MC-Unique: xSqx932FML6K_PkPDGbfjA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 34680C7408; Tue, 25 May 2021 07:40:36 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-113-228.ams2.redhat.com [10.36.113.228]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B3B6CE15D; Tue, 25 May 2021 07:40:34 +0000 (UTC) From: Florian Weimer To: Paul Eggert Cc: Adhemerval Zanella , libc-alpha@sourceware.org, Bruno Haible Subject: Re: [PATCH 3/3] Misc: Add and the cstack_* family of functions References: <73724441.XAIsEQcG03@omega> <146fa4f0-ea19-fdc4-a05c-74008bb4ab5f@linaro.org> Date: Tue, 25 May 2021 09:40:32 +0200 In-Reply-To: (Paul Eggert's message of "Mon, 24 May 2021 16:41:57 -0700") Message-ID: <87tumr1csv.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-6.7 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 25 May 2021 07:40:40 -0000 * Paul Eggert: > On 5/24/21 12:11 PM, Adhemerval Zanella via Libc-alpha wrote: > >> If this is really a requirement, I think the best options would be to add >> an extra flag to opt-in. > > Opt-in works for me. Although the GNU apps I help maintain typically > don't have nested functions, nested functions are a longstanding GNU C > feature and are a good thing to have when you need them. Since the requirement for non-executable stacks does not encapsulate well, I'd rather make this automatic if you think executable stack support is required. (The code allocating the stack might not know about the trampolines.) Thanks, Florian