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From: Eli Zaretskii <eliz@gnu.org>
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Subject: Re: Using static_assert in Emacs?
Date: Thu, 18 Jul 2024 20:35:44 +0300
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Cc: emacs-devel@gnu.org, eggert@cs.ucla.edu
To: Stefan Kangas <stefankangas@gmail.com>
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 (message from Stefan Kangas on Thu, 18 Jul 2024 09:39:43 -0700)
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> From: Stefan Kangas <stefankangas@gmail.com>
> Date: Thu, 18 Jul 2024 09:39:43 -0700
> Cc: emacs-devel@gnu.org, eggert@cs.ucla.edu
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > We already have it in config.h, so we can use it.  (Gnulib actually
> > uses it, see lib/*.c.)
> 
> Good to know, thanks.
> 
> > The real question is: where and how will that be useful?
> 
> I'm looking at something like this, where the sizes are known at compile
> time:
> 
>     #define FOO "some text"
>     static_assert (sizeof buf >= sizeof FOO);
>     memcpy (buf, FOO, sizeof FOO);

If we have such code (do we?), and if there's a danger that someone
makes FOO longer but forgets to change buf, such an assertion could be
useful.  IME, such code is rare, though.