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From: "wjwray at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/96185] Enhancement: Please add a builtin to count bindings
 in [dcl.struct.bind]
Date: Tue, 14 Jul 2020 15:39:23 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96185

--- Comment #6 from Will Wray <wjwray at gmail dot com> ---
Thanks for the comment on approach Jonathan:

I'd noticed some collaboration and agreement around previous builtins
such as __builtin_bit_cast which is now available in both GCC & Clang
(though with some small inevitable divergence of behaviour).

Clearly Richard's suggestion to prioritize P1061, with such illustrious
co-authorship, is the best solution. I can offer to help on the gcc side.
This is the std way to go.

This request was borne of some frustration; I miss this facility in C++20.
By a hack, Clang happens to support SFINAE on structured binding since v5
- lack of any way to do it in GCC prompted this request.
My thinking was that a builtin can see quicker implementation and adoption
than std features. This builtin _is_ in support of a std proposal.=