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Date: Wed, 10 Mar 2021 20:06:18 +0100
From: David Lamparter <equinox@diac24.net>
To: Martin Sebor <msebor@gmail.com>
Cc: gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH] c: don't drop typedef information in casts
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On Wed, Mar 10, 2021 at 08:02:16PM +0100, David Lamparter wrote:
> Also, in seeing your response re. the volatile, it occured to me that
> stripping qualifiers on a typedef and still calling it the typedef is
> unhelpful.  Ideally, my goal is:
> 
> typedef int i;
> typedef const int ci;
> typeof((i)x) = i
> typeof((ci)x) = int  (<-- w/ my patch = ci; this is confusing)

Clarification:  with the current patch, the type of (ci)x is *called*
"ci", but doesn't actually have the const qualifier.  That's the
confusing part.  The const (or volatile) is stripped off the typedef in
the added build_qualified_type() call, but that now-different type is
still referred to as "ci"...

> typeof((const i)x) = i