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//@ revisions: nofallback fallback
//@[nofallback] check-pass
#![cfg_attr(fallback, feature(never_type, never_type_fallback))]
fn make_unit() {}
trait Test {}
impl Test for i32 {}
impl Test for () {}
fn unconstrained_arg<T: Test>(_: T) {}
fn main() {
//[nofallback]~^ warn: this function depends on never type fallback being `()`
//[nofallback]~| warn: this was previously accepted by the compiler but is being phased out; it will become a hard error in Rust 2024 and in a future release in all editions!
// Here the type variable falls back to `!`,
// and hence we get a type error.
unconstrained_arg(return);
//[fallback]~^ ERROR trait bound `!: Test` is not satisfied
}
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