This test case: https://github.com/rust-lang/rust/blob/aa3ca1994904f2e056679fce1f185db8c7ed2703/src/test/ui/issue-20413.rs ``` trait Foo { fn answer(self); } struct NoData<T>; //~^ ERROR: parameter `T` is never used impl<T> Foo for T where NoData<T>: Foo { //~^ ERROR: overflow evaluating the requirement fn answer(self) { let val: NoData<T> = NoData; } } fn main() {} ``` Currently compiles fine with gccrs: https://godbolt.org/z/r3Poahqxj