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From: "StevenSun2021 at hotmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/99686] New: ICE when concepts on C++17 when providing both
 T&& and const T& specialization
Date: Sat, 20 Mar 2021 19:21:50 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99686

            Bug ID: 99686
           Summary: ICE when concepts on C++17 when providing both T&& and
                    const T& specialization
           Product: gcc
           Version: 10.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: StevenSun2021 at hotmail dot com
  Target Milestone: ---

This problem occurs only when using std=3Dc++17 and -fconcepts. It compiles=
 when
using std=3Dc++20.


I also have an online compiler link for this. https://godbolt.org/z/W9r6Wx

-------------------------------------------------------------------------
template <typename T>
void func(T &&arg)
{
}

template <typename T>
requires requires(T t) { ++t; }
void func(T &&arg)
{
}

template <>
void func(int &&arg)
{
}

template <>
void func(const int &arg)
{
}

int main()
{
    func(1); // I am expecting func(int&&)
}=