From patchwork Sun May 2 17:48:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Huth X-Patchwork-Id: 1472867 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=d5FW6Kie; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 4FYDDQ33Mxz9sCD for ; Mon, 3 May 2021 03:51:02 +1000 (AEST) Received: from localhost ([::1]:47176 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ldGFA-000304-Fa for incoming@patchwork.ozlabs.org; Sun, 02 May 2021 13:51:00 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48632) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ldGD7-0000Ie-8g for qemu-devel@nongnu.org; Sun, 02 May 2021 13:48:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:22874) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ldGD4-0000TP-78 for qemu-devel@nongnu.org; Sun, 02 May 2021 13:48:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619977729; 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=t65MeeZAzptBIeI41RhzkY73pzinSJ6z0ZbTAjGpghw=; b=d5FW6KiebO6XYaA3ZmnS9lg2ryvO4n39G5JXYGHrhlXCctCQfpEShdf0quzo6BFKkfsdz7 DXgFcPrQRxmIYQd1ZF35bR5GWasYsMKVWSq7UcTmlToftae1GVM+xX/qCyxEzozLrtzJQ7 AlxMmdEiOar7Zb9WfP/OmlQr0ydmhZQ= 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-499-viya5MnoPjqtF2BosMzBYg-1; Sun, 02 May 2021 13:48:45 -0400 X-MC-Unique: viya5MnoPjqtF2BosMzBYg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C065250200; Sun, 2 May 2021 17:48:44 +0000 (UTC) Received: from thuth.com (ovpn-112-16.ams2.redhat.com [10.36.112.16]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8351250F70; Sun, 2 May 2021 17:48:43 +0000 (UTC) From: Thomas Huth To: qemu-s390x@nongnu.org, Christian Borntraeger Subject: [PATCH 3/4] pc-bios/s390-ccw: Silence GCC 11 stringop-overflow warning Date: Sun, 2 May 2021 19:48:35 +0200 Message-Id: <20210502174836.838816-4-thuth@redhat.com> In-Reply-To: <20210502174836.838816-1-thuth@redhat.com> References: <20210502174836.838816-1-thuth@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 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 Received-SPF: pass client-ip=216.205.24.124; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.697, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Cornelia Huck , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Philippe Mathieu-Daudé When building on Fedora 34 (gcc version 11.0.0 20210210) we get: In file included from pc-bios/s390-ccw/main.c:11: In function ‘memset’, inlined from ‘boot_setup’ at pc-bios/s390-ccw/main.c:185:5, inlined from ‘main’ at pc-bios/s390-ccw/main.c:288:5: pc-bios/s390-ccw/libc.h:28:14: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=] 28 | p[i] = c; | ~~~~~^~~ The offending code is: memset((char *)S390EP, 0, 6); where S390EP is a const address: #define S390EP 0x10008 The compiler doesn't now how big that pointed area is, so assume its length is zero. This has been reported as BZ#99578 to GCC: "gcc-11 -Warray-bounds or -Wstringop-overread warning when accessing a pointer from integer literal" https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578 As this warning does us more harm than good in the BIOS code (where lot of direct accesses to low memory are done), silence this warning for all BIOS objects. Suggested-by: Thomas Huth Signed-off-by: Philippe Mathieu-Daudé Message-Id: <20210422145911.2513980-1-philmd@redhat.com> Acked-by: Christian Borntraeger [thuth: Use the pre-existing cc-option macro instead of adding a new one] Signed-off-by: Thomas Huth Reviewed-by: Cornelia Huck --- pc-bios/s390-ccw/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/pc-bios/s390-ccw/Makefile b/pc-bios/s390-ccw/Makefile index f0fe84c9eb..83fb1afb73 100644 --- a/pc-bios/s390-ccw/Makefile +++ b/pc-bios/s390-ccw/Makefile @@ -30,6 +30,7 @@ OBJECTS = start.o main.o bootmap.o jump2ipl.o sclp.o menu.o \ virtio.o virtio-scsi.o virtio-blkdev.o libc.o cio.o dasd-ipl.o QEMU_CFLAGS := -Wall $(filter -W%, $(QEMU_CFLAGS)) +QEMU_CFLAGS += $(call cc-option,-Werror $(QEMU_CFLAGS),-Wno-stringop-overflow) QEMU_CFLAGS += -ffreestanding -fno-delete-null-pointer-checks -fno-common -fPIE QEMU_CFLAGS += -fwrapv -fno-strict-aliasing -fno-asynchronous-unwind-tables QEMU_CFLAGS += $(call cc-option, $(QEMU_CFLAGS), -fno-stack-protector)