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=-12.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 47005C35669 for ; Sat, 22 Feb 2020 02:08:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 18BB3206E2 for ; Sat, 22 Feb 2020 02:08:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582337304; bh=zmW4SnTFdWF9ThHYGcitqrDsoBQVp8CyN2jzLEtj5n8=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=YCNZTr9mmfs9bb6B3eHppCoZAFL3YW7aiMdZDtknsv5WkhIHTO0QRITN5oz0BkCRB +BrAZeSCabjdW5EGSddV0U6RttPBh68GsfWX9bw0go1eAaFsXQvW+i4I7xd1pY/2jI dfu7o2Tj3mdHNYEKyJwZ5gt9Hxs8g4tKPuZu8oCc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727989AbgBVCII (ORCPT ); Fri, 21 Feb 2020 21:08:08 -0500 Received: from conssluserg-05.nifty.com ([210.131.2.90]:36492 "EHLO conssluserg-05.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727614AbgBVCIH (ORCPT ); Fri, 21 Feb 2020 21:08:07 -0500 Received: from mail-ua1-f48.google.com (mail-ua1-f48.google.com [209.85.222.48]) (authenticated) by conssluserg-05.nifty.com with ESMTP id 01M27pq0019695; Sat, 22 Feb 2020 11:07:52 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-05.nifty.com 01M27pq0019695 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1582337272; bh=TYeg4Bu2Cm4zg+SosHfJhXDl9NaBkIe9vTu10xXiyPY=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=siBi6422Adl4HyJFo6ewKwOUC7vv5+/KDzMJ27mMmcDRzcp/pXJ9cJFZhP/MkfcwG ADTyFeI6bBNqEVcQ+fxVnsuJdRr86WSfv0CaOkj7oKh9unZ754Xs948LPk3vTjmy8O ZHCJ+eTaRZ3bPxVp2sSWWKZtwU3MbxzQzXY2qkpSFMNxTJiz9pKjZpEqRhHXOyT4Z7 mUtrFUBKiX35d81vaYtzrata8Z3T7c/qYTTdX/1RdDyOvSW+hX8lj2gVyeGeFbpTlz TMRkI3QK8gsTsU4qpK9CrDU5vltT9uc5s7BsT8efaRsN3muLh+tkVAuBxOorB3xULL vmpLFciOtq7iw== X-Nifty-SrcIP: [209.85.222.48] Received: by mail-ua1-f48.google.com with SMTP id l6so1372325uap.13; Fri, 21 Feb 2020 18:07:51 -0800 (PST) X-Gm-Message-State: APjAAAWOjKhjRf4/GWkEtGsJ3NTpbSdtbZx96deCbe46u+x4OOTQLlOa xwpZe8jgQpWdNq07jddAspgOSu6Rn3kVtH5ByK4= X-Google-Smtp-Source: APXvYqy64BDtpJM6tCLKq1UaIlD4WE9x1BFzkNuYwRDuIYfuA4OQm5/DVZnxw4VhIskXXReLLHCvVmI6Fe+cQGDuKCY= X-Received: by 2002:ab0:2ea6:: with SMTP id y6mr20800352uay.25.1582337270650; Fri, 21 Feb 2020 18:07:50 -0800 (PST) MIME-Version: 1.0 References: <20200222003820.220854-1-alex_y_xu.ref@yahoo.ca> <20200222003820.220854-1-alex_y_xu@yahoo.ca> In-Reply-To: <20200222003820.220854-1-alex_y_xu@yahoo.ca> From: Masahiro Yamada Date: Sat, 22 Feb 2020 11:07:14 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] kbuild: move -pipe to global KBUILD_CFLAGS To: "Alex Xu (Hello71)" Cc: Linux Kbuild mailing list , Michal Marek , Linux Kernel Mailing List , Russell King 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 Sat, Feb 22, 2020 at 9:40 AM Alex Xu (Hello71) wrote: > > -pipe reduces unnecessary disk wear for systems where /tmp is not a > tmpfs, slightly increases compilation speed, and avoids leaving behind > files when gcc crashes. > > According to the gcc manual, "this fails to work on some systems where > the assembler is unable to read from a pipe; but the GNU assembler has > no trouble". We already require GNU ld on all platforms, so this is not > an additional dependency. LLVM as also supports pipes. > > -pipe has always been used for most architectures, this change > standardizes it globally. Most notably, arm, arm64, riscv, and x86 are > affected. > > Signed-off-by: Alex Xu (Hello71) > diff --git a/arch/arc/Makefile b/arch/arc/Makefile > index 20e9ab6cc521..b6a2f553771c 100644 > --- a/arch/arc/Makefile > +++ b/arch/arc/Makefile > @@ -9,7 +9,7 @@ ifeq ($(CROSS_COMPILE),) > CROSS_COMPILE := $(call cc-cross-prefix, arc-linux- arceb-linux-) > endif > > -cflags-y += -fno-common -pipe -fno-builtin -mmedium-calls -D__linux__ > +cflags-y += -fno-common -fno-builtin -mmedium-calls -D__linux__ > cflags-$(CONFIG_ISA_ARCOMPACT) += -mA7 > cflags-$(CONFIG_ISA_ARCV2) += -mcpu=hs38 > > diff --git a/arch/arm/Makefile b/arch/arm/Makefile > index db857d07114f..7711467e0797 100644 > --- a/arch/arm/Makefile > +++ b/arch/arm/Makefile > @@ -21,7 +21,6 @@ KBUILD_LDS_MODULE += $(srctree)/arch/arm/kernel/module.lds > endif > > GZFLAGS :=-9 > -#KBUILD_CFLAGS +=-pipe This was commented out by a very old commit, which is available in the historical git tree. https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=ce20ed858a20f6f04de475cae79e40d3697f4776 But, I could not parse the reason from the commit message. Russell, do you remember why? If arch maintainers are fine with this change, I can pick up it. Thanks. -- Best Regards Masahiro Yamada