// revisions: mirunsafeck thirunsafeck // [thirunsafeck]compile-flags: -Z thir-unsafeck #![allow(dead_code)] union U { a: u8, // OK } union W { a: String, //~ ERROR unions cannot contain fields that may need dropping b: String, // OK, only one field is reported } struct S(String); // `S` doesn't implement `Drop` trait, but still has non-trivial destructor union Y { a: S, //~ ERROR unions cannot contain fields that may need dropping } // We don't know if `T` is trivially-destructable or not until trans union J<T> { a: T, //~ ERROR unions cannot contain fields that may need dropping } union H<T: Copy> { a: T, // OK, `T` is `Copy`, no destructor } fn main() {}