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=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 CE576C2D0E5 for ; Sun, 29 Mar 2020 18:44:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A19A62076A for ; Sun, 29 Mar 2020 18:44:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728610AbgC2SnS (ORCPT ); Sun, 29 Mar 2020 14:43:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:42786 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728570AbgC2SnR (ORCPT ); Sun, 29 Mar 2020 14:43:17 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 DAAC920784; Sun, 29 Mar 2020 18:43:16 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.93) (envelope-from ) id 1jIctv-002Fqq-PS; Sun, 29 Mar 2020 14:43:15 -0400 Message-Id: <20200329184315.677608653@goodmis.org> User-Agent: quilt/0.65 Date: Sun, 29 Mar 2020 14:42:53 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Nick Desaulniers , Nathan Chancellor Subject: [for-next][PATCH 01/21] tracing: Use address-of operator on section symbols References: <20200329184252.289087453@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nathan Chancellor Clang warns: ../kernel/trace/trace.c:9335:33: warning: array comparison always evaluates to true [-Wtautological-compare] if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) ^ 1 warning generated. These are not true arrays, they are linker defined symbols, which are just addresses. Using the address of operator silences the warning and does not change the runtime result of the check (tested with some print statements compiled in with clang + ld.lld and gcc + ld.bfd in QEMU). Link: http://lkml.kernel.org/r/20200220051011.26113-1-natechancellor@gmail.com Link: https://github.com/ClangBuiltLinux/linux/issues/893 Suggested-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 6b11e4e2150c..02be4ddd4ad5 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -9334,7 +9334,7 @@ __init static int tracer_alloc_buffers(void) goto out_free_buffer_mask; /* Only allocate trace_printk buffers if a trace_printk exists */ - if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) + if (&__stop___trace_bprintk_fmt != &__start___trace_bprintk_fmt) /* Must be called before global_trace.buffer is allocated */ trace_printk_init_buffers(); -- 2.25.1