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=-3.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 96595C388F7 for ; Wed, 4 Nov 2020 00:18:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3E611223C6 for ; Wed, 4 Nov 2020 00:18:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LmBQY7CZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729997AbgKDASc (ORCPT ); Tue, 3 Nov 2020 19:18:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54446 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729189AbgKDARG (ORCPT ); Tue, 3 Nov 2020 19:17:06 -0500 Received: from mail-qk1-x742.google.com (mail-qk1-x742.google.com [IPv6:2607:f8b0:4864:20::742]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8063AC0613D1; Tue, 3 Nov 2020 16:17:06 -0800 (PST) Received: by mail-qk1-x742.google.com with SMTP id a65so15005702qkg.13; Tue, 03 Nov 2020 16:17:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=o7VW5Grk+dEY5JWkUUhDhbgHVtmwCHyugEP4jZ8aPsI=; b=LmBQY7CZqa1Au8AieLs3s89z+TAZTWFu47IyTFakjM14mtGBE0bIvq09IxUR/j+lGt jO2oFrnBfi6hhUoVlAdRtHXd+feaAlnZQr+9acvskwJFyP9euRoCyubnsP4LUYVTPpjW xD0WBBdEYKtHlh3zK9FCyH++TA8G+OswbpSEKDY/jVrRunpJ3A/4QOBbm+MhwnsO5TdV yqwwzbScJDd43N/mRTutzDVsjMQJPyWDc/EF++mSvkFmBuchKgHPYawKPBWHsTnoNCvx ly80xsFLIWLwxfJ3OXFIhDDhUB7tnL1rCq1ouhjTkQz1f8mqr3yewDFm0xEymE5CD4Ji l7sQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:date:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=o7VW5Grk+dEY5JWkUUhDhbgHVtmwCHyugEP4jZ8aPsI=; b=ZH8YcFK5T+S6O+gx2iaZqc+1sTEUQYoZbFSxLASNAowxIZW9jl7CEWRKXMWsjssA6t 37u2PwcOSkoeRHBXA72muYTaykAEErLPpdSsaFDubbuz1/6RwjDHId2oAPi1R66FaYNB jIessFa1WlzHFTx4Os+Tq1WnmTaMtO1AlH4ksWmtNXt/EOFd9L5o8175SiGX5bogYdrm Ha1ui0xs6kOfR14nQmGxXa9d/7Z/X1D5Ku0yBtk0M54SKZJnUDOKhMrmbaJDNWElI2O1 vEAVFykRL7kTuFZXOAVhS9JHn4O+HNQYRt2hdG3CSireWmcJK5bMGH7mKV/01eRpYLx3 ksGw== X-Gm-Message-State: AOAM530jIYMi4rEpAPu013o8d95R01xdlBDY5DZQ7dPqNtxkExvJvMIq vfmTd/X3yestdJeD1QZP8Sk= X-Google-Smtp-Source: ABdhPJxDxDTkiIxlaL7Qz6PndmDqbwNkUczXPhVDYLRk2J3zyu+p4VzbqK8EJ4e/Ty4zD1S2IOxfeA== X-Received: by 2002:ae9:e210:: with SMTP id c16mr21871175qkc.314.1604449025589; Tue, 03 Nov 2020 16:17:05 -0800 (PST) Received: from rani.riverdale.lan ([2001:470:1f07:5f3::b55f]) by smtp.gmail.com with ESMTPSA id y68sm655321qkb.38.2020.11.03.16.17.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Nov 2020 16:17:05 -0800 (PST) Sender: Arvind Sankar From: Arvind Sankar X-Google-Original-From: Arvind Sankar Date: Tue, 3 Nov 2020 19:17:03 -0500 To: Nick Desaulniers Cc: Arvind Sankar , Masahiro Yamada , Linux Kbuild mailing list , LKML , clang-built-linux , linux-toolchains@vger.kernel.org Subject: Re: [PATCH] Kbuild: implement support for DWARF5 Message-ID: <20201104001703.GA2407187@rani.riverdale.lan> References: <20201022012106.1875129-1-ndesaulniers@google.com> <20201104000016.GA2399651@rani.riverdale.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 03, 2020 at 04:05:36PM -0800, Nick Desaulniers wrote: > 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 This is giving me deja vu about the -gz=zlib option. Didn't Masahiro fix the cc-option issue with 4d0831e8a029 ("kconfig: unify cc-option and as-option") The existing -Wa,-gdwarf-2 in the Makefile seems bogus, btw. GCC 4.9.0 at least appears to pass on --gdwarf2 automatically.