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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Constants and undefined behavior
Date: Sat, 06 Jun 2026 15:47:07 -0700
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Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

> I claim that an expression that looks like a constant expression
> *isn't* a constant-expression if it doesn't appear in a context
> that requires a constant-expression.

Right.  This question came up years ago in a Defect Report.  The
response from the Committee was basically the same as what you
said:  the 6.6 constraints for constant expressions apply only in
situations where the C standard expressly requires a constant
expression.  (I don't have the DR in front of me;  I'm summarizing
based on memory, but am confident the actual wording is consistent
with what I just said.)