src/test/run-pass/issues/issue-30530.rs

   1 // run-pass
   2 // Regression test for Issue #30530: alloca's created for storing
   3 // intermediate scratch values during brace-less match arms need to be
   4 // initialized with their drop-flag set to "dropped" (or else we end
   5 // up running the destructors on garbage data at the end of the
   6 // function).
   7
   8 pub enum Handler {
   9     Default,
  10     #[allow(dead_code)]
  11     Custom(*mut Box<dyn Fn()>),
  12 }
  13
  14 fn main() {
  15     #[allow(unused_must_use)] {
  16         take(Handler::Default, Box::new(main));
  17     }
  18 }
  19
  20 #[inline(never)]
  21 pub fn take(h: Handler, f: Box<dyn Fn()>) -> Box<dyn Fn()> {
  22     unsafe {
  23         match h {
  24             Handler::Custom(ptr) => *Box::from_raw(ptr),
  25             Handler::Default => f,
  26         }
  27     }
  28 }