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From: James Kuyper <jameskuyper@alumni.caltech.edu>
Newsgroups: comp.lang.c
Subject: Re: So You Think You Can Const?
Date: Sat, 11 Jan 2025 10:58:44 -0500
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On 1/10/25 13:56, Keith Thompson wrote:
> David Brown <david.brown@hesbynett.no> writes:
> [...]
>> If you want a better signature for "free", then I would suggest "void
>> free(void ** p)" - that (to me) more naturally shows that the function
>> is freeing the pointer, while also greatly reducing the "use after
>> free" errors in C code by turning them into "dereferencing a null
>> pointer" errors which are more easily caught by many OS's.
>
> I'm not sure that would work. A void** argument means you need to pass
> a pointer to a void* object. If you've assigned the converted result of
> malloc() to, say, an int* object, you don't have a void* object. (int*
> and void* might not even have the same representation).

Correct. As a result, that interface would, in principle, require
storing the pointer in a void* object so that it's address could be
passed to free(). In many contexts, that would encourage saving the
original void* value returned by malloc() for passing to free(), while
creating a second pointer for actually using the allocated memory.