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 Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3E18BC53219 for ; Mon, 27 Jul 2026 19:37:22 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1woR8I-0004L0-HZ; Mon, 27 Jul 2026 15:37:02 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1woR8G-0004KX-0V for qemu-devel@nongnu.org; Mon, 27 Jul 2026 15:37:00 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1woR8E-0002XK-F8 for qemu-devel@nongnu.org; Mon, 27 Jul 2026 15:36:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1785181017; h=from:from: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=8enDtt8cqW6+NfaeAchD/r03eS4yL17OiwkOLzPRv3s=; b=ONTxhwbzDiq8gwTx5+env2sJTVqEl7gDwXN7gHUPXhqJkZ3mbEbMT5wpZo3HlL2he8f4XA Xa/0WRgHmadkAmpjnRcTZJhGmsXu2isABwzkSUOIqvPTr7pyshnc6qPezbliy95toCsYAk 9NAUiCC2lkjsx9/m/svp6D26xpi/3sQ= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-68-YNicFfhZPbKh_mFzC8sh7A-1; Mon, 27 Jul 2026 15:36:55 -0400 X-MC-Unique: YNicFfhZPbKh_mFzC8sh7A-1 X-Mimecast-MFC-AGG-ID: YNicFfhZPbKh_mFzC8sh7A_1785181014 Received: by mail-wm1-f71.google.com with SMTP id 5b1f17b1804b1-495689bfcc8so24053515e9.1 for ; Mon, 27 Jul 2026 12:36:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=google; t=1785181014; x=1785785814; darn=nongnu.org; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to:content-type; bh=8enDtt8cqW6+NfaeAchD/r03eS4yL17OiwkOLzPRv3s=; b=qPVNYm9isEG4sSouIEROcDk0cN4W7BWCbpWVCq0MYpxhnYqKhfNULmBYxf+PzfFXRt BrLD2IJZhksungXwXDjWe3oBb+ki5GW6BW2/sOvgZFzce7NDDgxGKYT4/DscNwL3XIZd easajPqq7rQKVGHfTErdhU6yf94oe1KGttFBuk0gU0H+R/830ohxZ4T1Kd95F9cVN+Id whpalEaV7k37ZaniAQeYJgVjef6vZIAMEiFfrAAbTq+wjANH1fyJMIGxUfEiLC2SMcPp Dw1fx2lbckHZdNl8TKPIMp44A+dJ2uPS7QW9e18lzRVh8YayG2fKf7gz724WkyMarP1n PFFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785181014; x=1785785814; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:from :date:x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=8enDtt8cqW6+NfaeAchD/r03eS4yL17OiwkOLzPRv3s=; b=gpitPndibMpDXB3CeIVjd0mtPJAy1oWuyWUEDCRvz+y+oPQUyxqY6xK1V36PYhmN9o lieeFqFf2FhHNDeEZB7vJ/ZTmAFLPRp15/Sh7dhMj8tvXAFdELXB5uErmuHhT7kGd1ar KZdF5vjViCMUJOwG2n0ywXs9amazLbE1X0HZHG7zQ4H1keTpVvsebujfN8nbkUJKGRL7 HaixqYLuLXovbdZZ6xOUhRhnvsM/YNDNLsSzOwRVpfe7D4vt1SfSaPIrSMQc+zcNFtlW pPJqx35bdSQGej+XwWTccPeNkFqrTS3pse1ULn8j+9GaiyCMi06830qL+66QaEaE2Etd aDTg== X-Gm-Message-State: AOJu0YyL/hojFKp3HngI8tAck71yarCq4RCPHJ/3PuCGHIyqwlhKQyet peRJ/M1gYHTk35FWLIaFeaAaF7ruydIfpVLbY1blYB+5+dsqtJW4YAucYy8BjQOiv66U3hCx08e pI5eQMYBBTnFfEyMQUv6Ov+QJUvLxsAEHI9k1BUu1Xr/3audB/aO+wGPQ X-Gm-Gg: AR+sD11/235O4/GtqA7ccHQhmJmx3GVLCUHQZgpOClD+k1WpUqG4z+YikbfuJDvphvO +WwsCByXbC4Mf6beeZcn8dhUcTodWc9GlRyzgt8zKzQkJk9zqqabtWFaCWxdWIABAY+m0HE5BUE TvhekeWhUYaHdEpJM+qFMF1d8Ksma/cZBvC3K2tCFYjd7DHG3S2MJzKMJ5Cd+oczJEvqFp/toVW lWJqpaZOnxn7co0YMyF54TF++xBl4NCXVbwvs08h3ASssvkjnFudRebwOAqpmyxL0hP/X2fqeeu PpQXJCJ5hTXSMdBxVAYzakWgiWs32KE2hBONYw7zMLOKxrEi3+mIrTlQzBiGpwQqTzCjmidhRQk Qa+5Mpe9Xgcr9Y/dBJT+R/A== X-Received: by 2002:a05:600c:1986:b0:495:5943:b76c with SMTP id 5b1f17b1804b1-496c4fe1f75mr4131185e9.34.1785181013940; Mon, 27 Jul 2026 12:36:53 -0700 (PDT) X-Received: by 2002:a05:600c:1986:b0:495:5943:b76c with SMTP id 5b1f17b1804b1-496c4fe1f75mr4130955e9.34.1785181013441; Mon, 27 Jul 2026 12:36:53 -0700 (PDT) Received: from redhat.com (IGLD-80-230-28-14.inter.net.il. [80.230.28.14]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4957bfe07e1sm252109975e9.3.2026.07.27.12.36.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jul 2026 12:36:52 -0700 (PDT) Date: Mon, 27 Jul 2026 15:36:48 -0400 From: "Michael S. Tsirkin" To: =?iso-8859-1?Q?Marc-Andr=E9?= Lureau Cc: qemu-devel@nongnu.org, Alex =?iso-8859-1?Q?Benn=E9e?= , Akihiko Odaki , Dmitry Osipenko , Stefan Hajnoczi , Kevin Wolf , Hanna Reitz , qemu-block@nongnu.org, Jonathan Cameron , Paolo Bonzini , Fam Zheng , Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= , Zhao Liu , Roman Bolshakov , Phil Dennis-Jordan , Wei Liu , linux-cxl@vger.kernel.org, Brian Cain , Pierrick Bouvier , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= , Peter Xu , Fabiano Rosas Subject: Re: [PATCH v2 03/12] block/blkio: fix compiler false-positive warning Message-ID: <20260727153554-mutt-send-email-mst@kernel.org> References: <20260727-fix2-v2-0-d0c4831ed7ea@redhat.com> <20260727-fix2-v2-3-d0c4831ed7ea@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260727-fix2-v2-3-d0c4831ed7ea@redhat.com> Received-SPF: pass client-ip=170.10.133.124; envelope-from=mst@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -36 X-Spam_score: -3.7 X-Spam_bar: --- X-Spam_report: (-3.7 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.58, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, Jul 27, 2026 at 12:44:02AM +0400, Marc-André Lureau wrote: > Under some optimization, gcc produces a false-positive: > ../block/blkio.c: In function ‘blkio_co_getlength’: > ../block/blkio.c:943:8: error: ‘ret’ may be used uninitialized [-Werror=maybe-uninitialized] > 943 | if (ret < 0) { > | ^ > > Replace WITH_QEMU_LOCK_GUARD with the simpler QEMU_LOCK_GUARD. > > Suggested-by: Akihiko Odaki > Signed-off-by: Marc-André Lureau or we can disable erroring out on these warnings with these "some optimization" options. the warning in question already questionable at best. > --- > block/blkio.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/block/blkio.c b/block/blkio.c > index 52a8be220d1c..4801339f98b2 100644 > --- a/block/blkio.c > +++ b/block/blkio.c > @@ -937,9 +937,8 @@ static int64_t coroutine_fn blkio_co_getlength(BlockDriverState *bs) > uint64_t capacity; > int ret; > > - WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { > - ret = blkio_get_uint64(s->blkio, "capacity", &capacity); > - } > + QEMU_LOCK_GUARD(&s->blkio_lock); > + ret = blkio_get_uint64(s->blkio, "capacity", &capacity); > if (ret < 0) { > return ret; > } > > -- > 2.55.0