From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B16C4C10DCE for ; Wed, 18 Mar 2020 14:28:08 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7B7E320772 for ; Wed, 18 Mar 2020 14:28:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UtQcd3zv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7B7E320772 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:51356 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jEZfz-0001V5-IS for qemu-devel@archiver.kernel.org; Wed, 18 Mar 2020 10:28:07 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55613) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jEZfP-0000zq-OE for qemu-devel@nongnu.org; Wed, 18 Mar 2020 10:27:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jEZfN-0001KE-Ge for qemu-devel@nongnu.org; Wed, 18 Mar 2020 10:27:30 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:58583) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jEZfN-0001Iz-6h for qemu-devel@nongnu.org; Wed, 18 Mar 2020 10:27:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1584541648; 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=SIwDEuAjkCkA6WQUeoeTLkCs7w9SadwAykRb8hXwIlM=; b=UtQcd3zvltQF5I0iP1a/8lLnHsJqGRC+O0VROE2pZzJ1gjaikTJdyDqI9l2CQPKXkVmGEl iEeck+DLUYpZylSPQHVPiXY1jH0SNnvMmFabUIh0+ZkFSy+kL+Earjglf5qIiX3q5CyC+M QkEyMzgl5QwfA191G8sYr4fK19fhcoY= 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-320-5wjga3nVOlW8xd0tR9fZiw-1; Wed, 18 Mar 2020 10:27:13 -0400 X-MC-Unique: 5wjga3nVOlW8xd0tR9fZiw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8C0AD1005509; Wed, 18 Mar 2020 14:27:10 +0000 (UTC) Received: from redhat.com (ovpn-115-92.ams2.redhat.com [10.36.115.92]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 49BF660BEC; Wed, 18 Mar 2020 14:27:03 +0000 (UTC) Date: Wed, 18 Mar 2020 14:26:54 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Vladimir Sementsov-Ogievskiy Subject: Re: [RFC (fix for 5.0?)] block/io: do not do pointer arithmetic on void * Message-ID: <20200318142654.GH2173309@redhat.com> References: <20200318142253.2809-1-vsementsov@virtuozzo.com> MIME-Version: 1.0 In-Reply-To: <20200318142253.2809-1-vsementsov@virtuozzo.com> User-Agent: Mutt/1.13.3 (2020-01-12) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 63.128.21.74 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: kwolf@redhat.com, fam@euphon.net, qemu-block@nongnu.org, qemu-devel@nongnu.org, mreitz@redhat.com, stefanha@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Mar 18, 2020 at 05:22:53PM +0300, Vladimir Sementsov-Ogievskiy wrot= e: > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- >=20 > Hi all! >=20 > C standard doesn't allow pointer arithmetic on void *. > Still, gcc allows it as an extension: > https://gcc.gnu.org/onlinedocs/gcc-4.8.0/gcc/Pointer-Arith.html >=20 > I can create a series of patches like this. Do we need it? I don't think so, we only care about gcc & clang. > Also, where is documented which compilers are supported by Qemu? It is checked in configure - gcc 4.8 or clang 3.4 or xcode clang 5.1 >=20 > block/io.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/block/io.c b/block/io.c > index aba67f66b9..539178aed5 100644 > --- a/block/io.c > +++ b/block/io.c > @@ -1277,7 +1277,7 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(Bd= rvChild *child, > * modifying the image file. This is critical for zero-copy guest I= /O > * where anything might happen inside guest memory. > */ > - void *bounce_buffer =3D NULL; > + char *bounce_buffer =3D NULL; > =20 > BlockDriver *drv =3D bs->drv; > int64_t cluster_offset; > --=20 > 2.21.0 >=20 >=20 Regards, Daniel --=20 |: https://berrange.com -o- https://www.flickr.com/photos/dberrange= :| |: https://libvirt.org -o- https://fstop138.berrange.com= :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange= :|