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Date:   Sat, 26 Jun 2021 02:37:24 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Miguel Ojeda <ojeda@kernel.org>
Subject: Re: [PATCH v2] ELF: add and use SUPPRESS_WARN_UNUSED_RESULT
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On Fri, Jun 25, 2021 at 07:05:58PM -0700, Linus Torvalds wrote:

> > Do we really care about userspace which relies upon an SVR4 quirk?  I
> > guess it's too hard to prove the no case, so it stays.
> 
> I think we can safely remove it. Doing a mmap() at address zero will
> not actually work anyway in any half-way modern Linux environment.
> 
> And I think the "map zeroes at NULL" wasn't even universal for SVr4.
> _Some_ binaries may have expected it, but I suspect it was the
> exception rather than the rule.
> 
> So I'd happily take a patch that just removes it. If nothing else, it
> would be trivial to put back if somebody screams, but I seriously
> doubt that is going to happen.

Wasn't there some emulator (dosemu? wine?) that relied upon that?
Said that, I could be easily wrong - half-asleep right now...