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From: Julio Di Egidio <julio@diegidio.name>
Newsgroups: comp.lang.c
Subject: Re: So You Think You Can Const?
Date: Thu, 9 Jan 2025 12:26:24 +0100
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On 09/01/2025 12:21, Keith Thompson wrote:
> Julio Di Egidio <julio@diegidio.name> writes:
>> On 08/01/2025 17:48, Andrey Tarasevich wrote:
> [...]
>>> It is perfectly safe. One can even argue that standard declaration
>>> if `free` as `void free(void *)` is defective. It should have been
>>> `void free(const void *)` from the very beginning.
>>
>> I do not understand that: `free` is changing the pointed data, so how
>> can `const void *` even be "correct"?
> 
> No, `free` doesn't (necessarily) change the pointed-to data.
> Any attempt to access the allocated data after free() has undefined
> behavior, 

I would indeed call that a change!

Anyway I see the point, thanks for explaining.

-Julio

> so it might be modified, but all free() needs to do is
> make it available for further allocation.  It might do so without
> touching the data itself.