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Subject: Re: Cleaning up numbering for new x86 syscalls?
To:     Ingo Molnar <mingo@kernel.org>, Andy Lutomirski <luto@kernel.org>
Cc:     X86 ML <x86@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        Borislav Petkov <bp@alien8.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Tycho Andersen <tycho@tycho.ws>,
        Daniel Colascione <dancol@google.com>,
        Florian Weimer <fweimer@redhat.com>,
        "Carlos O'Donell" <carlos@redhat.com>,
        Rich Felker <dalias@libc.org>
References: <CALCETrVPcgKarpTOsdTfODkNA76W04WvW+tNWoOx6+Em0KS04A@mail.gmail.com>
 <20181120073352.GA79825@gmail.com>
From:   Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Message-ID: <87cbf7b4-9e77-adc1-8e18-14dd206f0b79@petrovitsch.priv.at>
Date:   Wed, 21 Nov 2018 00:04:34 +0100
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On 20/11/2018 08:33, Ingo Molnar wrote:
[...]
> 6. Is x32 even used in practice? I still think it was a mistake to add it 
>    and some significant distributions like Fedora are not enabling it.

x32 works as far as gcc/gas/ld is concerned (at least for compiling
non-trivial programs).
Finding a distribution that actually *delivers* x32 libraries is another
thing (and said non-trivial software uses ATM e.g. libxml2) - at least I
can't find an "x32-Ubuntu".
And no, I don't see a compelling reason to (try to) build the n+1.
architecture for the major distributions.
And yes, lots of stuff will not compile out of the box (especially if
one uses a somewhat sane set of gcc options - not only -Wall -Wextra
-Werror) but if one gets software to compile for i386 and x86_64,
getting it to compile for x32 is a Friday afternoon job (more or less).
And yes, there is enough hardware/systems out there that uses 64bit CPUs
(for whatever reason - if only that one can't get a 32bit CPU for that
board) but will never ever need more than 2-3 GB RAM .....

MfG,
	Bernd
-- 
Bernd Petrovitsch                  Email : bernd@petrovitsch.priv.at
                     LUGA : http://www.luga.at