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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]:38242 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kXluE-0007z8-1f for qemu-devel@archiver.kernel.org; Wed, 28 Oct 2020 09:54:26 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51366) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kXlsf-0006fN-CB for qemu-devel@nongnu.org; Wed, 28 Oct 2020 09:52:50 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:22923) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kXlsa-00032u-1r for qemu-devel@nongnu.org; Wed, 28 Oct 2020 09:52:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1603893161; 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; 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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20201028041819.2169003-4-kuhn.chenqun@huawei.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=thuth@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/28 01:51:10 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 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, NICE_REPLY_A=-0.921, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action 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: , Cc: zhang.zhanghailiang@huawei.com, Riku Voipio , Richard Henderson , ganqixin@huawei.com, Euler Robot , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 28/10/2020 05.18, Chen Qun wrote: > When using -Wimplicit-fallthrough in our CFLAGS, the compiler showed warning: > ../accel/tcg/user-exec.c: In function ‘handle_cpu_signal’: > ../accel/tcg/user-exec.c:169:13: warning: this statement may fall through [-Wimplicit-fallthrough=] > 169 | cpu_exit_tb_from_sighandler(cpu, old_set); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > ../accel/tcg/user-exec.c:172:9: note: here > 172 | default: > > This exception branch fall through the 'default' branch and run the 'g_assert_not_reached' statement. > So we could use "fall through" instead of "NORETURN" here. > > Reported-by: Euler Robot > Signed-off-by: Chen Qun > --- > Cc: Riku Voipio > Cc: Richard Henderson > Cc: Paolo Bonzini > --- > accel/tcg/user-exec.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c > index 4ebe25461a..330468e990 100644 > --- a/accel/tcg/user-exec.c > +++ b/accel/tcg/user-exec.c > @@ -167,7 +167,7 @@ static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info, > */ > clear_helper_retaddr(); > cpu_exit_tb_from_sighandler(cpu, old_set); > - /* NORETURN */ > + /* fall through */ There should not be a fall through here since the previous function should never return. Does the warning go away if you mark the cpu_exit_tb_from_sighandler() function with QEMU_NORETURN ? If so, I think that would be the better fix. Thomas