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Re: [PATCH] Disable building with i386-*, -march=i386 or -mcpu=i386.
- From: "Carlos O'Donell" <carlos at redhat dot com>
- To: "Joseph S. Myers" <joseph at codesourcery dot com>
- Cc: GNU C Library <libc-alpha at sourceware dot org>, Roland McGrath <roland at hack dot frob dot com>, Andreas Jaeger <aj at suse dot com>, Thomas Schwinge <thomas at codesourcery dot com>
- Date: Thu, 28 Mar 2013 11:49:30 -0400
- Subject: Re: [PATCH] Disable building with i386-*, -march=i386 or -mcpu=i386.
- References: <513FE49D dot 3050406 at redhat dot com> <Pine dot LNX dot 4 dot 64 dot 1303131610540 dot 19781 at digraph dot polyomino dot org dot uk> <51526E77 dot 4040801 at redhat dot com> <Pine dot LNX dot 4 dot 64 dot 1303271431550 dot 23096 at digraph dot polyomino dot org dot uk>
On 03/27/2013 10:35 AM, Joseph S. Myers wrote:
> On Tue, 26 Mar 2013, Carlos O'Donell wrote:
>
>> +# Configure for i686 if the user asks for i386. We don't support
>> +# i386 any more but it continues to be common for users to configure
>> +# 32-bit x86 as i386. We build for i686 instead.
>> +if test "$machine" = i386; then
>> + machine="i686"
>
> Wouldn't i486 be more conservative?
It would be, but in truth *everyone* I've talked to wants i686.
The distros build for i686, users use i686, there is no real use
of i486 or i586 that I can see.
Therefore I would like the elision of i386 to be to a value i686
which has real value for users and is a sensible default in 99%
of the cases. Defaulting to i486 or i586 might be more conservative
but is less useful.
What do you think? Is it valid to balance usefullness in this way?
> Really, given this change, I think sysdeps/i386/i486 should be merged into
> sysdeps/i386, and likewise for nptl/sysdeps/i386/i486 and
> nptl/sysdeps/unix/sysv/linux/i386/i486, since i486 will be the minimum
> supported x86 processor. Given that, there would be no real point setting
> machine to i486 since there wouldn't be i486 sysdeps directories any more.
> If you don't do that followup moving of files, it should at least go on
> the wiki / Bugzilla as a todo item.
I agree. I'd actually like to rename i386 to x86 and merge i486 down
in two steps.
I will admit that I *tried* to merge i486 down a directory but found
that it was considerably more work than I had anticipated.
If you agree that eliding i386 to i686 is acceptable then I'll file
a BZ with the details of my initial work to remove i386, and add it
to the master todo list.
Cheers,
Carlos.