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From: "anders.granlund.0 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/97375] Unexpected top-level const retainment when declaring non-type template paramter with decltype(auto)
Date: Wed, 14 Oct 2020 07:35:02 +0000	[thread overview]
Message-ID: <bug-97375-4-qR2gSJkncO@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-97375-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97375

--- Comment #1 from Anders Granlund <anders.granlund.0 at gmail dot com> ---
Here is another example of the same problem without using decltype(auto), so
the problem seems to be more general:

  #include <iostream>
  #include <type_traits>

  template<const int I>
  void f1()
  {
    std::cout << std::is_const_v<decltype(I)> << std::endl;
  }

  template<typename T, T I>
  void f2()
  {
    std::cout << std::is_const_v<decltype(I)> << std::endl;
  }

  int main()
  {
    f1<0>(); // Outputs: 0 Ok
    f2<const int, 0>(); // Outputs: 1 Not ok. Should output 0 also.
  }

Compiler explorer link for this example: https://godbolt.org/z/8ah1ax

  parent reply	other threads:[~2020-10-14  7:35 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-12  3:37 [Bug c++/97375] New: " anders.granlund.0 at gmail dot com
2020-10-12  7:42 ` [Bug c++/97375] " marxin at gcc dot gnu.org
2020-10-14  7:35 ` anders.granlund.0 at gmail dot com [this message]
2021-06-09 14:20 ` mpolacek at gcc dot gnu.org

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