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From: Andreas Schwab <schwab@linux-m68k.org>
To: DJ Delorie <dj@redhat.com>
Cc: alx@kernel.org,  libc-alpha@sourceware.org
Subject: Re: free(3) const void *
Date: Fri, 26 Jan 2024 23:07:50 +0100	[thread overview]
Message-ID: <87y1cb3g09.fsf@igel.home> (raw)
In-Reply-To: <xnle8bsr5x.fsf@greed.delorie.com> (DJ Delorie's message of "Fri, 26 Jan 2024 16:47:38 -0500")

On Jan 26 2024, DJ Delorie wrote:

> Andreas Schwab <schwab@linux-m68k.org> writes:
>> Also, objects in the heap are never read-only.
>
> I thought of that, but using "const" in a program can mean something
> other than "the object is read-only".

Right, that is the difference between const-qualified and read-only.

> It can also act as a promise to the user and/or optimizer that an
> object is not written to, even if doing such is possible.

Unfortunately, the C standard does not support that promise.  Only
static or automatic objects can be truely read-only.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."

  reply	other threads:[~2024-01-26 22:07 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-26 13:21 Alejandro Colomar
2024-01-26 14:24 ` Arsen Arsenović
2024-01-26 15:35   ` Alejandro Colomar
2024-01-26 17:22     ` Arsen Arsenović
2024-01-26 17:55       ` Xi Ruoyao
2024-01-26 18:11         ` Alejandro Colomar
2024-01-26 20:04           ` Arsen Arsenović
2024-01-26 20:07         ` Arsen Arsenović
2024-01-26 17:40     ` Andreas Schwab
2024-01-26 19:45     ` Florian Weimer
2024-01-26 15:13 ` Andreas Schwab
2024-01-26 15:33   ` Alejandro Colomar
2024-01-26 18:09 ` Russ Allbery
2024-01-26 18:23   ` Alejandro Colomar
2024-01-26 18:36     ` Xi Ruoyao
2024-01-26 18:40       ` Alejandro Colomar
2024-01-26 18:49         ` Xi Ruoyao
2024-01-26 18:57           ` Alejandro Colomar
2024-01-26 18:40     ` Russ Allbery
2024-01-26 18:45       ` Alejandro Colomar
2024-01-26 19:41   ` Florian Weimer
2024-01-26 18:39 ` [PATCH] Use [[gnu::access(none)]] on free(3) Alejandro Colomar
2024-01-26 18:41   ` Alejandro Colomar
2024-01-26 21:23     ` Paul Eggert
2024-01-26 23:19       ` Alejandro Colomar
2024-01-27 13:21       ` Cristian Rodríguez
2024-02-13 15:19         ` Gabriel Ravier
2024-02-13 15:28           ` Alejandro Colomar
2024-01-26 21:11 ` free(3) const void * DJ Delorie
2024-01-26 21:30   ` Andreas Schwab
2024-01-26 21:47     ` DJ Delorie
2024-01-26 22:07       ` Andreas Schwab [this message]
2024-01-26 23:25       ` Alejandro Colomar

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