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From: "andrew.n.sutton at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/66841] [concepts] bogus error "invalid reference to function concept" when function concept is overloaded
Date: Sun, 12 Jul 2015 20:40:00 -0000	[thread overview]
Message-ID: <bug-66841-4-Q2bAZoBY47@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-66841-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66841

--- Comment #1 from Andrew Sutton <andrew.n.sutton at gmail dot com> ---
The program is ill-formed. In this line:

   requires Constructible<T, Args...>() // ERROR HERE

There's no single declaration of Constructible that can be matched to those
template arguments. You would need one with this signature: <typename T,
typename... Args>.

I think defining Constructible so that it backends into a type trait will give
you the behavior you're looking for.

template<typename T, typename... Args>
concept bool Constructible() {
  return std::is_constructible<T, Args...>::value;
}


  reply	other threads:[~2015-07-12 20:40 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-07-11 18:17 [Bug c++/66841] New: " eric.niebler at gmail dot com
2015-07-12 20:40 ` andrew.n.sutton at gmail dot com [this message]
2015-07-12 20:44 ` [Bug c++/66841] " eric.niebler at gmail dot com
2015-08-04 13:37 ` jason at gcc dot gnu.org

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