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From: Florian Weimer <fweimer@redhat.com>
To: Ville Voutilainen <ville.voutilainen@gmail.com>
Cc: Jonathan Wakely <jwakely@redhat.com>,  Alejandro Colomar
 <colomar.6.4.3@gmail.com>,  gcc@gcc.gnu.org,  "libstdc++"
 <libstdc++@gcc.gnu.org>,  Libc-alpha <libc-alpha@sourceware.org>,
 libc-coord@lists.openwall.com
Subject: Re: Expose 'array_length()' macro in <sys/param.h>
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Date: Tue, 22 Sep 2020 13:40:42 +0200
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 (Ville Voutilainen's message of "Tue, 22 Sep 2020 01:13:57 +0300")
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* Ville Voutilainen:

> Why should this be array_length and not __array_length? This is a
> vendor extension, so it should use
> a name that is reserved for such?

In general, we use __ for glibc internals that are not intended for
direct access by users.  In some cases, we have non-__ identifiers that
are redirected to these __ identifiers.

In some cases it may be beneficial to expose vendor extensions under __
names, so that they can be used in strict standard modes, but we are
quite far away from that for C++ at least.

Thanks,
Florian
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