From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: sparse-llvm array size computation issue
Date: Wed, 29 Mar 2017 09:41:06 -0700
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To: Dibyendu Majumdar <mobile@majumdar.org.uk>
Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>, Linux-Sparse <linux-sparse@vger.kernel.org>

On Wed, Mar 29, 2017 at 9:21 AM, Dibyendu Majumdar
<mobile@majumdar.org.uk> wrote:
>
> I am trying out an approach. If a SYM_NODE has a base type of SYM_NODE
> then which of the nodes should be used as the source for information
> you mention?

Does that actually happen? It shouldn't. A symbol node contains the C
name of the symbol, but you should never have a SYM_NODE that points
to another SYM_NODE, it always points to some actual type (ie ptr,
whatever).

So the rule should be that the node can have specific information
about that particular named symbol (so: name, array size, modifiers,
address space, initializer etc), and then the node->ctype.base_type
should point to a non-NODE symbol describing the base type.

But maybe I forget some special case. Things like 'typeof() can be
complicated, but we should be peeling things off so that we only ever
have one level of SYM_NODE.

                Linus