From owner-freebsd-hackers  Thu Jun  7 10:47:54 2001
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Date: Thu, 7 Jun 2001 12:47:30 -0500
From: "Jacques A. Vidrine" <n@nectar.com>
To: John Baldwin <jhb@FreeBSD.org>
Cc: Peter Pentchev <roam@orbitel.bg>, hackers@FreeBSD.org
Subject: Re: free() and const warnings
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References: <20010607195634.I724@ringworld.oblivion.bg> <XFMail.010607102051.jhb@FreeBSD.org>
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On Thu, Jun 07, 2001 at 10:20:51AM -0700, John Baldwin wrote:
> 
> On 07-Jun-01 Peter Pentchev wrote:
> > On Thu, Jun 07, 2001 at 07:07:22PM +0300, Peter Pentchev wrote:
> >> Hi,
> >> 
> >> Is free((void *) (size_t) ptr) the only way to free a const whatever *ptr
> >> with WARNS=2?  (or more specifically, with -Wcast-qual)
> > 
> > Uhm.  OK.  So size_t may not be enough to hold a pointer.  What is it then -
> > caddr_t?
> 
> uintptr_t for data pointers.  In theory I think code pointers may not fit in a
> uintptr_t.

C99 says of uintptr_t only that for any valid pointer p, the following
is true:

    (void *)(uintptr_t)p == (void *)p

Likewise for  intptr_t.  I read  that as  covering both code  and data
pointers.

Of  course, who's  to  say the  way uintptr_t  is  implemented on  our
platform adheres to the same rules :-)


> free((void *)(uintptr_t)ptr) should work.
> 
> Of course, this begs the question of why you are free'ing a const. :)

Indeed!

Cheers,
-- 
Jacques Vidrine / n@nectar.com / jvidrine@verio.net / nectar@FreeBSD.org

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