Rollup merge of #36140 - cristicbz:test-14875, r=nagisa

Add test for #14875

You can check this out in the playground https://is.gd/oVKC2T . It will fail on stable, but pass on nightly as @nagisa suggested on the issue.

Fixes #14875

src/test/run-pass/issue-14875.rs

@@ -0,0 +1,43 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Check that values are not leaked when a dtor panics (#14875)
+
+use std::panic::{self, UnwindSafe};
+
+struct SetInnerOnDrop<'a>(&'a mut bool);
+
+impl<'a> UnwindSafe for SetInnerOnDrop<'a> {}
+
+impl<'a> Drop for SetInnerOnDrop<'a> {
+    fn drop(&mut self) {
+        *self.0 = true;
+    }
+}
+
+struct PanicOnDrop;
+impl Drop for PanicOnDrop {
+    fn drop(&mut self) {
+        panic!("test panic");
+    }
+}
+
+
+fn main() {
+    let mut set_on_drop = false;
+    {
+        let set_inner_on_drop = SetInnerOnDrop(&mut set_on_drop);
+        let _ = panic::catch_unwind(|| {
+            let _set_inner_on_drop = set_inner_on_drop;
+            let _panic_on_drop = PanicOnDrop;
+        });
+    }
+    assert!(set_on_drop);
+}