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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 143FBC38A30 for ; Tue, 21 Apr 2020 01:14:04 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C54C0208E4 for ; Tue, 21 Apr 2020 01:14:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="S+SjrG63" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C54C0208E4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6D8368E000E; Mon, 20 Apr 2020 21:14:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 688D48E0003; Mon, 20 Apr 2020 21:14:03 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5C9288E000E; Mon, 20 Apr 2020 21:14:03 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0071.hostedemail.com [216.40.44.71]) by kanga.kvack.org (Postfix) with ESMTP id 3D37F8E0003 for ; Mon, 20 Apr 2020 21:14:03 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 002465821 for ; Tue, 21 Apr 2020 01:14:02 +0000 (UTC) X-FDA: 76730090724.22.suit68_5d87209f14812 X-HE-Tag: suit68_5d87209f14812 X-Filterd-Recvd-Size: 2527 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf26.hostedemail.com (Postfix) with ESMTP for ; Tue, 21 Apr 2020 01:14:02 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B291D2084D; Tue, 21 Apr 2020 01:14:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587431642; bh=Zwvy5kc1ydhKnK/Ovqv7ywWCprtPXz6qIWhfzNTk/mo=; h=Date:From:To:Subject:In-Reply-To:From; b=S+SjrG63diN5UrL5SsXR4Evz/Pho9MyDB0KINMkSvFRWdjmRpolzKCE9rGU2HKak+ fFdFFqUguinON/zR5gi6pXrHKp63EMEw52QCiLrSBiAk1UG3M27jkyiPuy3pZYJ1Qt VfzX/JnDDDWQ/3BclbVac2VVJnaFhvb68dG8UNTI= Date: Mon, 20 Apr 2020 18:14:01 -0700 From: Andrew Morton To: akpm@linux-foundation.org, gbiv@google.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, ndesaulniers@google.com, torvalds@linux-foundation.org Subject: [patch 08/15] tools/build: tweak unused value workaround Message-ID: <20200421011401.UOadM_a5p%akpm@linux-foundation.org> In-Reply-To: <20200420181310.c18b3c0aa4dc5b3e5ec1be10@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: George Burgess IV Subject: tools/build: tweak unused value workaround Clang has -Wself-assign enabled by default under -Wall, which always gets -Werror'ed on this file, causing sync-compare-and-swap to be disabled by default. The generally-accepted way to spell "this value is intentionally unused," is casting it to `void`. This is accepted by both GCC and Clang with -Wall enabled: https://godbolt.org/z/qqZ9r3 Link: http://lkml.kernel.org/r/20200414195638.156123-1-gbiv@google.com Signed-off-by: George Burgess IV Cc: Nick Desaulniers Signed-off-by: Andrew Morton --- tools/build/feature/test-sync-compare-and-swap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/tools/build/feature/test-sync-compare-and-swap.c~tools-build-tweak-unused-value-workaround +++ a/tools/build/feature/test-sync-compare-and-swap.c @@ -7,7 +7,7 @@ int main(int argc, char *argv[]) { uint64_t old, new = argc; - argv = argv; + (void)argv; do { old = __sync_val_compare_and_swap(&x, 0, 0); } while (!__sync_bool_compare_and_swap(&x, old, new)); _