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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Safety of casting from 'long' to 'int'
Date: Tue, 05 May 2026 06:41:43 -0700
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cross@spitfire.i.gajendra.net (Dan Cross) writes:

> [...] Or, something _can_ become UB that was not
> initially;  a program who took care to avoid UB in the ANSI C
> sense might find their program suddenly stops working because a
> thing they did became UB in a later revision of the standard
> (e.g., `realloc(0, ...)` becoming UB in C23).

Do you have another example?  In my view the change related to
realloc(0,...) is more a basis for condemning the decisions of
people on the C23 committee than it is a basis for condemning
the concept of undefined behavior.