message: Release of an Undef local is fine, and a NOP
diff: @@ -11,7 +11,7 @@ use super::{
  EvalError, EvalResult, EvalErrorKind,
  EvalContext, DynamicLifetime,
  AccessKind, LockInfo,
  - Value,
  + PrimVal, Value,
  Lvalue, LvalueExtra,
  Machine,
  };
  @@ -179,6 +179,7 @@ impl<'a, 'tcx, M: Machine<'tcx>> EvalContext<'a, 'tcx, M> {
  }
  }
  + // Release of an Undef local is fine, and a NOP.
  // HACK: For now, bail out if we hit a dead local during recovery (can happen because sometimes we have
  // StorageDead before EndRegion).
  // TODO: We should rather fix the MIR.
  @@ -186,7 +187,8 @@ impl<'a, 'tcx, M: Machine<'tcx>> EvalContext<'a, 'tcx, M> {
  Lvalue::Local { frame, local } => {
  let res = self.stack[frame].get_local(local);
  match (res, mode) {
  - (Err(EvalError{ kind: EvalErrorKind::DeadLocal, ..}), ValidationMode::Recover(_)) => {
  + (Err(EvalError{ kind: EvalErrorKind::DeadLocal, ..}), ValidationMode::Recover(_)) |
  + (Ok(Value::ByVal(PrimVal::Undef)), ValidationMode::Release) => {
  return Ok(());
  }
  _ => {},
  