From mboxrd@z Thu Jan  1 00:00:00 1970
From: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Subject: Re: [PATCH v2 00/27] LLVM fixes
Date: Sat, 11 Mar 2017 23:30:56 +0100
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To: Dibyendu Majumdar <mobile@majumdar.org.uk>
Cc: Jeff Garzik <jeff@garzik.org>, Linux-Sparse <linux-sparse@vger.kernel.org>, Christopher Li <sparse@chrisli.org>, Pekka Enberg <penberg@kernel.org>

On Sat, Mar 11, 2017 at 09:21:34PM +0000, Dibyendu Majumdar wrote:
> On 11 March 2017 at 20:44, Luc Van Oostenryck > But there is still
> some bad issues that remains,
> > for example pointer subtraction with NULL and some
> > optimization that destroy correct typing info.
> > They're bad enough to make me doubt of the value of this change.
> >
> > Here are some failing cases:
> >         #define NULL ((void *)0)
> >         int  tst(int  *ip) { return !ip; }
> >         int  foo(int  *ip) { return ip != NULL; }
> >         long bar(void *vp) { return vp - NULL; }
> >         long baz(int  *ip) { return ip - ((int *)0); }
> >
> 
> I only get a failure on the last one. But I am synced with master - so
> it may be an issue with sparse-next branch?

It's on my development branch:
	next
	+ today's 2nd serie
	+ today's 1st serie - 2 patches now unneeded.
So it's normal that you don't the same.

> For the last one, looks like linearized output is incorrect?
> 
> baz:
> .L6:
>         <entry-point>
>         divs.64     %r13 <- %arg1, $4
>         scast.32    %r14 <- (64) %r13
>         ret.32      %r14

It's not incorrect, only that the scast is unneeded.
But strangely, I don't see that cast here.

-- Luc