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Date:   Tue, 11 Dec 2018 21:38:15 +0100
From:   Shawn Rutledge <s@ecloud.org>
To:     linux-kernel@vger.kernel.org
Subject: Re: Can we drop upstream Linux x32 support?
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I like the idea of x32 in theory: any machine with 4GB or less of memory
for sure does not really need to waste any precious space storing 64-bit
pointers; and even if more memory is available, software that needs to
access more than 4GB per process is somewhat rare (as it should be).  I
used a laptop every day with 4GB until recently, so was generally trying to
run relatively lean software.  I have played around with the Gentoo x32
variant on another machine, just to see how that would go.  I haven't used
it for much...  but tried out some basic things; and as long as it is
powered on, it functions fine as a node in an icecream cluster, too.
The icecream statistics shown in icemon tell me that this machine seems to
be performing faster than it should be, for its age.  So I think there is
some worthwhile average speedup (without being more scientific about it).

As a Qt developer, I have some interest that Qt and Qt Quick ought to work
well on this architecture.  (When it breaks, I write up bugs like
QTBUG-52658 and QTBUG-42759.)  There is still no JIT support for QML, but
perhaps there could be (I could try, if I ever find time to learn how the
existing QML/V4 JIT works on other architectures well enough to add another
one); and meanwhile, at least the interpreter works AFAIK.  I was just
thinking of testing this again, maybe running gentoo or debian x32 on that
old 4GB laptop; so I did a quick google search, and found this thread right
away.

Linux supports a lot of rarely-used hardware and features; so as long as
the burden of supporting x32 is not too great, I'd like to put in my vote to
keep it working.  And I will keep testing from time to time and do my bit
to keep Qt working on this architecture, as long as I'm not wasting my time
(if it's going to disappear, it would be a waste of time).

I can't explain why there aren't more users, and more distros.  It seems
to me it would be a good choice for the compact or small-is-beautiful
distros, like Puppy.

(CC me on this thread if you like, since I'm not currently subscribed to LKML)