[Bug c++/121777] [15/16 Regression] ICE with returning a generic lambda to a template function

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121777

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |14.3.0
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2025-09-03
             Status|UNCONFIRMED                 |NEW
            Summary|ICE with returning a        |[15/16 Regression] ICE with
                   |generic lambda to a         |returning a generic lambda
                   |template function           |to a template function
      Known to fail|                            |15.1.0
           Keywords|                            |needs-bisection

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Reduced testcase:
```
template <class T> auto f() {
  return [](auto&& x) -> T { return (T) x; };
}

void test() {
  f<const int&>();
}
```