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Subject: Re: Expose 'array_length()' macro in <sys/cdefs.h> or <sys/param.h>
To:     Joseph Myers <joseph@codesourcery.com>
Cc:     libc-alpha@sourceware.org, libc-coord@lists.openwall.com,
        libstdc++ <libstdc++@gcc.gnu.org>, gcc@gcc.gnu.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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        Jonathan Wakely <jwakely@redhat.com>,
        Florian Weimer <fweimer@redhat.com>,
        Ville Voutilainen <ville.voutilainen@gmail.com>,
        enh@google.com, Rusty Russell <rusty@rustcorp.com.au>,
        Alejandro Colomar <colomar.6.4.3@gmail.com>
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 <alpine.DEB.2.21.2009301557590.5720@digraph.polyomino.org.uk>
From:   Alejandro Colomar <colomar.6.4.3@gmail.com>
Message-ID: <1aa963ec-0f44-4948-d862-7808b0b86a7a@gmail.com>
Date:   Wed, 30 Sep 2020 22:39:08 +0200
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On 2020-09-30 17:58, Joseph Myers wrote:
> For some reason http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2529.pdf
> doesn't seem to have reached the agenda of a WG14 meeting yet, but adding
> a language feature like that to the standard would be another approach.
> 

Hi Joseph,

Yes, that would be great!

I hope they add that to the language. When/if that happens, nitems() 
could be `#define nitems(arr) _Lengthof(arr)` for std >= c2x.

In the meantime, I would add this macro to libc.

Maybe gcc could add such a great feature as an extension even before the 
standard does...

Too many wishes :)

BTW, I sent a PATCH v4 that I should've sent --in-reply-to PATCH v3 in 
this thread (but I forgot to do so); I'll link to it here:

https://sourceware.org/pipermail/libc-alpha/2020-September/117986.html

Thanks,

Alex