src/test/ui/pattern/usefulness/always-inhabited-union-ref.rs

   1 // The precise semantics of inhabitedness with respect to unions and references is currently
   2 // undecided. This test file currently checks a conservative choice.
   3
   4 #![feature(exhaustive_patterns)]
   5 #![feature(never_type)]
   6
   7 #![allow(dead_code)]
   8 #![allow(unreachable_code)]
   9
  10 pub union Foo {
  11     foo: !,
  12 }
  13
  14 fn uninhab_ref() -> &'static ! {
  15     unimplemented!()
  16 }
  17
  18 fn uninhab_union() -> Foo {
  19     unimplemented!()
  20 }
  21
  22 fn match_on_uninhab() {
  23     match uninhab_ref() {
  24         //~^ ERROR non-exhaustive patterns: type `&!` is non-empty
  25     }
  26
  27     match uninhab_union() {
  28         //~^ ERROR non-exhaustive patterns: type `Foo` is non-empty
  29     }
  30 }
  31
  32 fn main() {}