Re: free(3) const void *

[Alejandro Colomar <alx@kernel.org>]

[-- Attachment #1: Type: text/plain, Size: 1049 bytes --]

Hi Arsen,

On Fri, Jan 26, 2024 at 03:24:29PM +0100, Arsen Arsenović wrote:
> But, free() modifies the object passed to it (even if not its bit
> representation) by freeing it.  Freeing const-passed objects would also
> violate the constness promise, so I disagree that free should take const
> void*.

This is an interesting interpretation.  Is expiring the lifetime of an
object a modification of the object?  Possibly.

But, the standard says:

	If an attempt is made to modify an object defined with a
	const-qualified type through use of an lvalue with
	non-const-qualified type, the behavior is undefined.

Even if you consider expiring the lifetime of the object a modification
of the object, the part that says "through use of an lvalue with
non-const-qualified type" is not fulfilled, IMO.  That would reqire
dereferencing the pointer, to actually get the lvalue, which free(3)
never does.

Have a lovely day,
Alex

-- 
<https://www.alejandro-colomar.es/>
Looking for a remote C programming job at the moment.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]