From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Subject: Re: [PATCH V2 00/19] C-SKY(csky) Linux Kernel Port Date: Fri, 13 Jul 2018 11:23:12 +0100 Message-ID: <11103.1531477392@warthog.procyon.org.uk> References: <5731b5c4-e29d-30f6-095f-4a74f52cb72d@codesourcery.com> <27030.1531302693@warthog.procyon.org.uk> <20180712125152.GA5226@guoren> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: In-Reply-To: <5731b5c4-e29d-30f6-095f-4a74f52cb72d@codesourcery.com> Content-ID: <11102.1531477392.1@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: Sandra Loosemore Cc: dhowells@redhat.com, Guo Ren , linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, daniel.lezcano@linaro.org, jason@lakedaemon.net, arnd@arndb.de, c-sky_gcc_upstream@c-sky.com, gnu-csky@mentor.com, thomas.petazzoni@bootlin.com, wbx@uclibc-ng.org, green.hu@gmail.com List-Id: linux-arch.vger.kernel.org Sandra Loosemore wrote: > I'm not familiar with the Fedora tools, but to build a complete toolchain > you'll need library support as well and I'm not sure what the submission > status/plans for that are. The idea behind the cross-gcc package in Fedora is that it's for kernel builds and bootloader-type things only. It builds libgcc, but doesn't use kernel headers or a C library[*] as this enormously simplifies things. The reasons being: (1) Not all arches can use the same set of C libraries (some can't use glibc and some don't have a uClibc port). (2) I can only build each individual compiler against a single C library - so if you have two or more incompatible environments, you're out of luck - I can only use one. (3) Building lots more compilers for individual environments would massively increase the build size and time. A full cross-gcc build now takes the best part of a day to build. [*] Yes, there's one exception: it builds the arm compiler against an arm cross-glibc - not my idea. David From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:34068 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727071AbeGMKhR (ORCPT ); Fri, 13 Jul 2018 06:37:17 -0400 From: David Howells In-Reply-To: <5731b5c4-e29d-30f6-095f-4a74f52cb72d@codesourcery.com> References: <5731b5c4-e29d-30f6-095f-4a74f52cb72d@codesourcery.com> <27030.1531302693@warthog.procyon.org.uk> <20180712125152.GA5226@guoren> Subject: Re: [PATCH V2 00/19] C-SKY(csky) Linux Kernel Port MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <11102.1531477392.1@warthog.procyon.org.uk> Date: Fri, 13 Jul 2018 11:23:12 +0100 Message-ID: <11103.1531477392@warthog.procyon.org.uk> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Sandra Loosemore Cc: dhowells@redhat.com, Guo Ren , linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, daniel.lezcano@linaro.org, jason@lakedaemon.net, arnd@arndb.de, c-sky_gcc_upstream@c-sky.com, gnu-csky@mentor.com, thomas.petazzoni@bootlin.com, wbx@uclibc-ng.org, green.hu@gmail.com Message-ID: <20180713102312.D5OANl8bf9oA7R0EmoH82w52qJuskmH0_xa2ikBlM5c@z> Sandra Loosemore wrote: > I'm not familiar with the Fedora tools, but to build a complete toolchain > you'll need library support as well and I'm not sure what the submission > status/plans for that are. The idea behind the cross-gcc package in Fedora is that it's for kernel builds and bootloader-type things only. It builds libgcc, but doesn't use kernel headers or a C library[*] as this enormously simplifies things. The reasons being: (1) Not all arches can use the same set of C libraries (some can't use glibc and some don't have a uClibc port). (2) I can only build each individual compiler against a single C library - so if you have two or more incompatible environments, you're out of luck - I can only use one. (3) Building lots more compilers for individual environments would massively increase the build size and time. A full cross-gcc build now takes the best part of a day to build. [*] Yes, there's one exception: it builds the arm compiler against an arm cross-glibc - not my idea. David