#![deny(where_clauses_object_safety)] trait Trait {} trait X { fn foo(&self) where Self: Trait; //~ ERROR the trait `X` cannot be made into an object //~^ WARN this was previously accepted by the compiler but is being phased out } impl X for () { fn foo(&self) {} } impl Trait for dyn X {} pub fn main() { // Check that this does not segfault. ::foo(&()); }