[Bug c++/97010] New: C++20 ADL and function templates that are not visible (P0846R0) fails on call with templated type

[kirshamir at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97010

            Bug ID: 97010
           Summary: C++20 ADL and function templates that are not visible
                    (P0846R0) fails on call with templated type
           Product: gcc
           Version: 10.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: kirshamir at gmail dot com
  Target Milestone: ---

#include <iostream>
#include <tuple>

template<class Tuple>
void print(const Tuple& tup) {
    // P0846R0: ADL should work here correctly
    std::cout << get<0>(tup) << std::endl; // fails with gcc
}

int main() {
    auto two_ints = std::make_tuple(1, 2);
    std::cout << get<0>(two_ints) << std::endl;  // ok
    print(two_ints);
}

Code: https://godbolt.org/z/YGGaEo