From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: MPS: assertion failed: header_type (h) != IGC_OBJ_FWD Date: Tue, 16 Jul 2024 18:22:22 +0300 Message-ID: <86sew9gy4x.fsf@gnu.org> References: <86zfqhh2xv.fsf@gnu.org> <87msmhwhal.fsf@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="4330"; mail-complaints-to="usenet@ciao.gmane.io" Cc: eller.helmut@gmail.com, eggert@cs.ucla.edu, pipcet@protonmail.com, emacs-devel@gnu.org To: Gerd =?utf-8?Q?M=C3=B6llmann?= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Jul 16 17:23:08 2024 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1sTk16-0000Xq-HK for ged-emacs-devel@m.gmane-mx.org; Tue, 16 Jul 2024 17:23:00 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sTk0Z-0003Bi-EF; Tue, 16 Jul 2024 11:22:27 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sTk0X-000374-8w for emacs-devel@gnu.org; Tue, 16 Jul 2024 11:22:25 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sTk0W-0008AD-Qp; Tue, 16 Jul 2024 11:22:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=MIME-version:References:Subject:In-Reply-To:To:From: Date; bh=9XrE0n5pjOnAsTjuZC/74mbZy0vqNvA4FVWkgolcKfU=; b=BYJ14hWgMKlUgV63hlNT VD8i0u2EY7ozFNv0zBZm52D5JyvJ+5ccAaPXsUrSBtivWX9Kp+TNleTOvGZPP1OGTfTrV0bBgafp6 ECXYcnsjquQkvNEaCX9tjOUTDf3Uj5eIo8bmZMKC2ikFVPa5LKB0ccL6H3Hftwf8HZddP0SiRp2+Q eaqq4NZeaQBT5JauuicjGYDFFLs7y0hx2JMxs3OMgCAVrfZkJPGquK/UgRe9ED3QRDwt7am7G7c// PRxO7Q0/QKBPnFNYc+WjpetRisHjyrz7pFZLpaEiB8a5IENYjctTVkhYoYg2tfV1/VMMQcnhi/Tiy 6bfkVAQ3KghBug==; In-Reply-To: (message from Gerd =?utf-8?Q?M=C3=B6llmann?= on Tue, 16 Jul 2024 16:48:38 +0200) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:321713 Archived-At: > From: Gerd Möllmann > Cc: Eli Zaretskii , Paul Eggert , > pipcet@protonmail.com, emacs-devel@gnu.org > Date: Tue, 16 Jul 2024 16:48:38 +0200 > > Helmut Eller writes: > > > On Tue, Jul 16 2024, Gerd Möllmann wrote: > > > >> That's probably a misunderstanding. I'm thinking about a block of memory > >> containing references, and the alignment of these references, not the > >> alignment of the block. > >> > >> Example with sizeof(int) = 4, and sizeof(void *) = 8 > >> > >> struct x > >> { > >> int x; > >> struct Lisp_Symbol *s; > >> }; > >> > >> What about the offset of x::s? > > > > That's not a problem because offsetof(struct x, s) = 8. There are 4 > > bytes padding after x. A problem could be if an unaligned void* is cast > > to a struct Lisp_Symbol*; let's hope that nobody does that. > > If you're right, and the same holds for the control stack and anything > else a malloc'd block can contain, then we're safe. > > Since I don't know that for a fact, it's an invalid assumption for me, ATM. I think it's a fact.