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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 20B1DC43331 for ; Thu, 26 Mar 2020 22:18:06 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1F41320658 for ; Thu, 26 Mar 2020 22:18:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1F41320658 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48pKB26L4fzDqWs for ; Fri, 27 Mar 2020 09:18:02 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=permerror (SPF Permanent Error: Unknown mechanism found: ip:192.40.192.88/32) smtp.mailfrom=kernel.crashing.org (client-ip=63.228.1.57; helo=gate.crashing.org; envelope-from=segher@kernel.crashing.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by lists.ozlabs.org (Postfix) with ESMTP id 48pK8Q6FJdzDqCT for ; Fri, 27 Mar 2020 09:16:38 +1100 (AEDT) Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 02QMGQUE031114; Thu, 26 Mar 2020 17:16:26 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 02QMGPkn031113; Thu, 26 Mar 2020 17:16:25 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Thu, 26 Mar 2020 17:16:25 -0500 From: Segher Boessenkool To: Fangrui Song Subject: Re: [PATCH v2] powerpc/boot: Delete unneeded .globl _zimage_start Message-ID: <20200326221625.GA22482@gate.crashing.org> References: <20200325164257.170229-1-maskray@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200325164257.170229-1-maskray@google.com> User-Agent: Mutt/1.4.2.3i X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alan Modra , Nick Desaulniers , clang-built-linux@googlegroups.com, Joel Stanley , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, Mar 25, 2020 at 09:42:57AM -0700, Fangrui Song wrote: > .globl sets the symbol binding to STB_GLOBAL while .weak sets the > binding to STB_WEAK. GNU as let .weak override .globl since binutils-gdb > 5ca547dc2399a0a5d9f20626d4bf5547c3ccfddd (1996). Clang integrated > assembler let the last win but it may error in the future. GNU AS works for more than just ELF. The way the assembler language is defined, it is not .weak overriding .globl -- instead, .weak sets a symbol attribute. On an existing symbol (but it creates on if there is none yet). Clang is buggy if it does not allow valid (and perfectly normal) assembler code like this. Segher