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=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 82541C169C4 for ; Mon, 11 Feb 2019 19:27:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E405218A1 for ; Mon, 11 Feb 2019 19:27:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="P0PqT7xL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732366AbfBKT1d (ORCPT ); Mon, 11 Feb 2019 14:27:33 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:37648 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731677AbfBKT1d (ORCPT ); Mon, 11 Feb 2019 14:27:33 -0500 Received: by mail-pf1-f196.google.com with SMTP id y126so29698pfb.4 for ; Mon, 11 Feb 2019 11:27:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=UNDCAdXK5WwzSSlG7lMjdTQ2ibEWaEc6ZQu2po9nEM0=; b=P0PqT7xLj5zeJXUuD/tUXOHefZC17cCQlVyOxsOC4ooVCULHGQXirYouvRmw4C9QDW A/t8CmKiCkLb/m8cQ1yzTUascDLpMR9KW8/qAJQDycAhcBQikRS1Np9vx/gfmDDGNtVJ RpxRo0c9Zp/r9dDOAEznSDlygOc5hblQsIBJcuSmOzh8PUH95afKlgHW81tyHOU0zy4J zjoRr2G6hqYgTJJMDaXMYD65RU99I84/yzvxd1nVdKI1PYX8gOIDkFib/ueJ820rltD5 TbF/0A3B5OYuIqvgaHP2kYy9Ys1iyeJJEM4iPFuQvR0NtIwZGcD4EAkN6QTYtiywSSPH OKhg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=UNDCAdXK5WwzSSlG7lMjdTQ2ibEWaEc6ZQu2po9nEM0=; b=cozDuhmZ2lKy1wmJZkX7rwnUjokvp08PypihJikWbj3NS8XVt2HY+qZQyv7ZZR7AyO c/RNqYHPNZqsF/3sPeQMiod8/7HEIh3WQzBOmO0BSuVG+aZdIXs3FR6AeQShyZDOai4B ET3WOGFqoybjoJZJaQxZtHKxUBMfYGO+cpw4HRrfJhDr+xlCfCeiK5Ng91N/GOgNIavH SKnXGYoG9nVbnfA66/yXDqsV6Vw/OrAI4FlKE2+BtBzoAhDMdWZmXwwa/0i1SFTD6pw5 PPmLav9wIi9lt5ihj9gMiN8kyYChPvgv2R+NHBhU/7hdkJj0A34Q8r2Bw3cqvPrDVG/S q6Dg== X-Gm-Message-State: AHQUAubfhYDJenfvj4D2u/jfiVIGac3wCcuGzkSpoexzWb3Cek8zkm+u bGNo0Yj9AyWQNXQIu0Zh2Z1BNH5YGMkoU3Jo2UcFpg== X-Google-Smtp-Source: AHgI3IZ007fXkqJrkaNyxZ/Ub8wtD9Zj1oMrGI0q72DeSdnz1SSC3WJqvffvdevp5uqqfmE+lCNcBUMy8EaQnpgQ54s= X-Received: by 2002:a62:2c81:: with SMTP id s123mr37868430pfs.174.1549913252158; Mon, 11 Feb 2019 11:27:32 -0800 (PST) MIME-Version: 1.0 References: <20190207220155.81351-1-ndesaulniers@google.com> <20190207220155.81351-3-ndesaulniers@google.com> <20190208055059.GD9647@archlinux-ryzen> In-Reply-To: From: Nick Desaulniers Date: Mon, 11 Feb 2019 11:27:20 -0800 Message-ID: Subject: Re: [PATCH 3/4] Makefile: lld: tell clang to use lld To: Masahiro Yamada Cc: Nathan Chancellor , Michal Marek , Linux Kbuild mailing list , LKML , Sedat Dilek 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 On Mon, Feb 11, 2019 at 7:33 AM Masahiro Yamada wrote: > > On Sat, Feb 9, 2019 at 2:27 AM Nick Desaulniers wrote: > > > > On Thu, Feb 7, 2019 at 9:51 PM Nathan Chancellor > > wrote: > > > > > > On Thu, Feb 07, 2019 at 02:01:51PM -0800, ndesaulniers@google.com wrote: > > > > This is needed because clang doesn't select which linker to use based on > > > > $LD but rather -fuse-ld=$(LD). This is problematic especially for > > > > cc-ldoption, which checks for linker flag support via invoking the > > > > compiler, rather than the linker. > > What do you mean by 'problematic' ? > > I see no build error in > arch/arm64/kernel/vdso/Makefile, at least. > > Clang uses BFD linker by default, > which may not match to the $(LD) passed in. > > Is this what you mean? Right, when using a linker other than BFD, we want cc-ldoption to tell us whether that linker supports a linker flag or not. -- Thanks, ~Nick Desaulniers