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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: "Catch-23: The New C Standard,Sets the World on Fire" by Terence Kelly with Special Guest Borer Yekai Pan
Date: Tue, 02 May 2023 06:22:50 -0700
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Ben Bacarisse <ben.usenet@bsb.me.uk> writes:

[context]

>> "Catch-23:  The New C Standard,Sets the World on Fire"
>>     https://queue.acm.org/detail.cfm?id=3588242

> I agree with the authors that the change declaring realloc(..., 0)
> to be undefined is worrying, but I can't follow their reasoning
> about the history.  They suggest something had already happened in
> C17 that set C on a course towards this "breaking change" but I
> can't find what they refer to.

After reviewing the paper again, and also consulting the C17
draft (n2176), I believe they meant to refer to this item, in
section 7.31.12, paragraph 2:

    Invoking realloc with a size argument equal to zero is an
    obsolescent feature.

The change to being obsolescent is mentioned in the paper, along
with a reference to the n2176 draft, in the last sentence of the
second to last paragraph before the "Muddling Through" section.