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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/103923] is_invocable<const T &, ...> inexplicably fails
Date: Thu, 06 Jan 2022 09:39:44 +0000	[thread overview]
Message-ID: <bug-103923-4-F7TZDbuxUE@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103923-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103923

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Here's a minimal program showing the underlying problem:

template<typename T, bool x = noexcept(T{}())>
struct C
{
};

struct T {
  struct H {
    auto operator()() const { return 0; }
  };
  C<H> c;
};

T t;

103923.C:1:43: error: use of 'auto T::H::operator()() const' before deduction
of 'auto'
    1 | template<typename T, bool x = noexcept(T{}())>
      |                                        ~~~^~
103923.C:10:12: error: template argument 2 is invalid
   10 |         C<H> c;
      |            ^

  parent reply	other threads:[~2022-01-06  9:39 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-05 23:16 [Bug c++/103923] New: " jengelh at inai dot de
2022-01-05 23:19 ` [Bug libstdc++/103923] " pinskia at gcc dot gnu.org
2022-01-06  9:23 ` redi at gcc dot gnu.org
2022-01-06  9:31 ` redi at gcc dot gnu.org
2022-01-06  9:37 ` redi at gcc dot gnu.org
2022-01-06  9:39 ` redi at gcc dot gnu.org [this message]
2022-01-06  9:46 ` redi at gcc dot gnu.org
2022-01-06 14:30 ` redi at gcc dot gnu.org
2022-01-06 14:53 ` redi at gcc dot gnu.org
2022-01-06 16:00 ` redi at gcc dot gnu.org

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