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=-11.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 B5B1EC2D0A3 for ; Wed, 4 Nov 2020 00:05:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7239A223C6 for ; Wed, 4 Nov 2020 00:05:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="R0wn1eCK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729843AbgKDAFz (ORCPT ); Tue, 3 Nov 2020 19:05:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729189AbgKDAFu (ORCPT ); Tue, 3 Nov 2020 19:05:50 -0500 Received: from mail-pg1-x542.google.com (mail-pg1-x542.google.com [IPv6:2607:f8b0:4864:20::542]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF69AC0613D1 for ; Tue, 3 Nov 2020 16:05:48 -0800 (PST) Received: by mail-pg1-x542.google.com with SMTP id u4so3193511pgr.9 for ; Tue, 03 Nov 2020 16:05:48 -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=IDPVpMjjQxmT8T6bAuv5nGEF9Cscu1+LLKKWzkBSO0s=; b=R0wn1eCKGkIpdF7qPMDWF5Y9Lb9R6jSyf6aZRAPk7alVldWDSe6WLYFH7QJcvpVRpm D7Uh6sXlkwLfIzghi5mWA+Z/7XrrJT0Iq6QAIEDLibW6egy5U6Ee128wcKtYdNd9JlMM yRQgCt0QRnApGeusxYpJwHkb1DMFCIkH4SLvv/WD3WZEtYvurV6XVNpBEgG10mpABTgq 5v4Sj5nZlvuQcLpjc0t76D6IsFMNUzqy4K2wKNK21U5z9DARW8Lgg+zxgDkrl5HhPMhp Y3NEOMCnJVFsVM8I4IT/y4mZiMratvIMIvIwtJA3qu5gDI5ILmOlQrA1A37nVxAO5wEz yyGA== 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=IDPVpMjjQxmT8T6bAuv5nGEF9Cscu1+LLKKWzkBSO0s=; b=ij3tmVWkeICGz1eyzZWNB/dzl8qVuJDofFblNbzX7rcdxcUqlTpG4/nsC4VVNUtKF5 6WkdDUcVqnJKhrJ4wm3G63JM85WVWfWlq3sOkHt69+3zD9z1B8uO0UtexO6vfWDdYRiK UOURejrpi8p+aGeXuAbksXGvJsVake8fvORpKbdBd1lHAkYvGivqAr46cvFJh9Tv1Ve6 0ocwHOuj+EpUI9U9+LvMWq6BklPjgy+48kjpZLnIWbMqQCiB5M9TOqdVcMqY6r0fAlDT C8ZyDbUp82j8NOfhRsV6sE9v7mbz9JQYhhmtQZfx2iDB1d1fxSj9OYEjZNxtt8cPV8QF sOiQ== X-Gm-Message-State: AOAM531HGMHkA4Y+ZpUClLfp4Y1cRcK/uoV3C7avCC68Tj+HO6M2bpAN QHGU8FOhR5j0FmtFOtR6dfuK+76+dtcnWWqrDWZc7Q== X-Google-Smtp-Source: ABdhPJx0JWeFLR32JFqyWMucOaCuuoT6BwNLjsxdj20SI+yVYY/HHcBG6kAPgHnBrdZbPJLKe90CxK/dZv7AsQA7ooA= X-Received: by 2002:a17:90a:6b04:: with SMTP id v4mr1725520pjj.101.1604448347880; Tue, 03 Nov 2020 16:05:47 -0800 (PST) MIME-Version: 1.0 References: <20201022012106.1875129-1-ndesaulniers@google.com> <20201104000016.GA2399651@rani.riverdale.lan> In-Reply-To: <20201104000016.GA2399651@rani.riverdale.lan> From: Nick Desaulniers Date: Tue, 3 Nov 2020 16:05:36 -0800 Message-ID: Subject: Re: [PATCH] Kbuild: implement support for DWARF5 To: Arvind Sankar Cc: Masahiro Yamada , Linux Kbuild mailing list , LKML , clang-built-linux , linux-toolchains@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-toolchains@vger.kernel.org On Tue, Nov 3, 2020 at 4:00 PM Arvind Sankar wrote: > > On Wed, Oct 21, 2020 at 06:21:06PM -0700, Nick Desaulniers wrote: > > Further -gdwarf-X where X is an unsupported value doesn't > > produce an error in $(CC). > > Do you have more details here? On godbolt.org, gcc does report an error > for unsupported dwarf versions. > > https://godbolt.org/z/G35798 > > gcc does not seem to pass the -gdwarf-* options to the assembler when > compiling C source. For assembler, gcc will pass an appropriate option > depending on the version of binutils it was configured with: if the > assembler doesn't support dwarf-5 it can call it with --gdwarf2 for eg. > > If the user is using a properly configured toolchain it doesn't look > like it should be an issue to just use cc-option? I wrote the base patch back in May, and didn't revisit until recently. I could have sworn the cc-option silently failed for the check cc-option does, which is /dev/null input. I need to recheck that, but it doesn't hurt to simply include it for now, which I've done in a v2 I'm about to send. -- Thanks, ~Nick Desaulniers