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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 45A87C00A8F for ; Tue, 24 Oct 2023 10:37:57 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qvEmx-0002Av-GB; Tue, 24 Oct 2023 06:37:31 -0400 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 1qvEmq-0002Ai-7H for qemu-devel@nongnu.org; Tue, 24 Oct 2023 06:37:24 -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 1qvEml-0006We-3d for qemu-devel@nongnu.org; Tue, 24 Oct 2023 06:37:23 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1698143838; 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: in-reply-to:in-reply-to:references:references; bh=o0W9SC7zLulE00xImu3yY1ham0zMrWduM2JwP5hX+uY=; b=K7n9+OScPQjg0EasXomBLMYZVnQOFFa2pe6pW5X12yNWSedLUEAG5hUP+BaylFAu8SabSh i2ZusQUfqCnMLaEuD6qMR842iSsL1o92u363sJYVrr8CydLB5sTHK7F0iPw2azt7PJYaZj L6ufPozzpTbJVyRt6qLnZemh5HQkMp4= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-74-Dg9EZsW9MD6eC0aLRoX7Bg-1; Tue, 24 Oct 2023 06:37:15 -0400 X-MC-Unique: Dg9EZsW9MD6eC0aLRoX7Bg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 17A8C2824762; Tue, 24 Oct 2023 10:37:15 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.193.56]) by smtp.corp.redhat.com (Postfix) with ESMTPS id EA7AA8C0A; Tue, 24 Oct 2023 10:37:14 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id E3B4221E6A1F; Tue, 24 Oct 2023 12:37:13 +0200 (CEST) From: Markus Armbruster To: Thomas Huth Cc: Hanna Reitz , Kevin Wolf , qemu-devel@nongnu.org, qemu-block@nongnu.org Subject: Re: [PATCH v2] block/snapshot: Fix compiler warning with -Wshadow=local References: <20231023175038.111607-1-thuth@redhat.com> <87zg08vcwd.fsf@pond.sub.org> Date: Tue, 24 Oct 2023 12:37:13 +0200 In-Reply-To: <87zg08vcwd.fsf@pond.sub.org> (Markus Armbruster's message of "Tue, 24 Oct 2023 06:54:10 +0200") Message-ID: <875y2ws3vq.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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_NONE=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: 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 Markus Armbruster writes: > Thomas Huth writes: > >> No need to declare a new variable in the the inner code block >> here, we can re-use the "ret" variable that has been declared >> at the beginning of the function. With this change, the code >> can now be successfully compiled with -Wshadow=local again. >> >> Fixes: a32e781838 ("Mark bdrv_snapshot_fallback() and callers GRAPH_RDLOCK") >> Signed-off-by: Thomas Huth >> --- >> v2: Assign "ret" only in one spot >> >> block/snapshot.c | 6 ++---- >> 1 file changed, 2 insertions(+), 4 deletions(-) >> >> diff --git a/block/snapshot.c b/block/snapshot.c >> index 6e16eb803a..55974273ae 100644 >> --- a/block/snapshot.c >> +++ b/block/snapshot.c >> @@ -629,7 +629,6 @@ int bdrv_all_goto_snapshot(const char *name, >> while (iterbdrvs) { >> BlockDriverState *bs = iterbdrvs->data; >> AioContext *ctx = bdrv_get_aio_context(bs); >> - int ret = 0; >> bool all_snapshots_includes_bs; >> >> aio_context_acquire(ctx); >> @@ -637,9 +636,8 @@ int bdrv_all_goto_snapshot(const char *name, >> all_snapshots_includes_bs = bdrv_all_snapshots_includes_bs(bs); >> bdrv_graph_rdunlock_main_loop(); >> >> - if (devices || all_snapshots_includes_bs) { >> - ret = bdrv_snapshot_goto(bs, name, errp); >> - } >> + ret = (devices || all_snapshots_includes_bs) ? >> + bdrv_snapshot_goto(bs, name, errp) : 0; >> aio_context_release(ctx); >> if (ret < 0) { >> bdrv_graph_rdlock_main_loop(); > > Better. Unconditional assignment to @ret right before it's checked is > how we should use @ret. > > Reviewed-by: Markus Armbruster > > And queued. Thanks! Mind if I drop the Fixes: tag? Nothing broken until we enable -Wshadow=local...