Re: [PATCH 5/5] add setting gs/fsbase

[Samuel Thibault]

Sergey Bugaev, le ven. 21 avril 2023 12:17:54 +0300, a ecrit:
> Hello,
> 
> On Fri, Apr 21, 2023 at 12:01 AM Samuel Thibault
> <samuel.thibault@gnu.org> wrote:
> > BTW, which dynamic linker path do we have set for x86_64-gnu?
> 
> It's in gcc/config/i386/gnu64.h in GCC tree:
> 
> #define GNU_USER_DYNAMIC_LINKER64 "/lib/ld-x86-64.so.1"
> 
> It was added by Flavio.

Ok, so it has the version, good :)

> So let's maybe choose a single path and use it consistently?

That's the one we should be using.

> I would also expect distros to want to have a say in this.

No, they don't :) otherwise they wouldn't respect the ABI. The AMD64
ABI indeed defaults to /lib/ld64.so.1, and says that Linux uses
/lib64/ld-linux-x86-64.so.2, and that is cast in stone, we cannot change
it any more.

/lib/ld-x86-64.so.1 should be completely fine.

> For instance on Debian GNU/Linux x86_64 ld.so is at
> /usr/lib/x86_64-linux-gnu/ld-2.31.so,

That's just where the file is stored. It's normal to set a symlink where
it is actually looked up.

> Which maybe makes sense if they wish to keep binaries built on Debian
> runnable on other distros. Do we want the same for Debian GNU/Hurd,

Better have a cross-distribution ABI, yes.

Samuel