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From:   David Howells <dhowells@redhat.com>
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To:     Sandra Loosemore <sandra@codesourcery.com>
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Subject: Re: [PATCH V2 00/19] C-SKY(csky) Linux Kernel Port
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Date:   Fri, 13 Jul 2018 11:23:12 +0100
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Sandra Loosemore <sandra@codesourcery.com> 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