#![feature(rustc_attrs)] #![feature(staged_api)] #![stable(feature = "a", since = "1.0.0")] #[rustc_promotable] #[stable(feature = "a", since = "1.0.0")] #[rustc_const_stable(feature = "a", since = "1.0.0")] pub const fn id(x: &'static T) -> &'static T { x } #[rustc_promotable] #[stable(feature = "a", since = "1.0.0")] #[rustc_const_stable(feature = "a", since = "1.0.0")] pub const fn new_string() -> String { String::new() } #[rustc_promotable] #[stable(feature = "a", since = "1.0.0")] #[rustc_const_stable(feature = "a", since = "1.0.0")] pub const fn new_manually_drop(t: T) -> std::mem::ManuallyDrop { std::mem::ManuallyDrop::new(t) } const C: () = { let _: &'static _ = &id(&new_string()); //~^ ERROR destructor of `String` cannot be evaluated at compile-time //~| ERROR: temporary value dropped while borrowed //~| ERROR: temporary value dropped while borrowed let _: &'static _ = &new_manually_drop(new_string()); //~^ ERROR: temporary value dropped while borrowed }; fn main() { let _: &'static _ = &id(&new_string()); //~^ ERROR: temporary value dropped while borrowed //~| ERROR: temporary value dropped while borrowed let _: &'static _ = &new_manually_drop(new_string()); //~^ ERROR: temporary value dropped while borrowed }