[Bug c++/100589] function with trailing return type must specify return type 'auto' instead of 'concept auto'

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100589

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-05-14
           Keywords|                            |accepts-invalid
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Please provide the testcase here, not just via a URL, as requested by
https://gcc.gnu.org/bugs/.

Here's the code, which is accepted with -std=c++20 but shouldn't be:

template<class T>
concept false_concept = false;

false_concept auto f() -> int;