1 files changed, 38 insertions, 0 deletions
diff --git a/src/test/ui/span/issue28498-reject-trait-bound.rs b/src/test/ui/span/issue28498-reject-trait-bound.rs
new file mode 100644
index 000000000..444cebb19
--- /dev/null
+++ b/src/test/ui/span/issue28498-reject-trait-bound.rs
@@ -0,0 +1,38 @@
+// Demonstrate that having a trait bound causes dropck to reject code
+// that might indirectly access previously dropped value.
+//
+// Compare with run-pass/issue28498-ugeh-with-trait-bound.rs
+
+use std::fmt;
+
+#[derive(Debug)]
+struct ScribbleOnDrop(String);
+
+impl Drop for ScribbleOnDrop {
+    fn drop(&mut self) {
+        self.0 = format!("DROPPED");
+    }
+}
+
+struct Foo<T: fmt::Debug>(u32, T);
+
+impl<T: fmt::Debug> Drop for Foo<T> {
+    fn drop(&mut self) {
+        // Use of `may_dangle` is unsound, because we access `T` fmt method when we pass
+        // `self.1` below, and thus potentially read from borrowed data.
+        println!("Dropping Foo({}, {:?})", self.0, self.1);
+    }
+}
+
+fn main() {
+    let (last_dropped, foo0);
+    let (foo1, first_dropped);
+
+    last_dropped = ScribbleOnDrop(format!("last"));
+    first_dropped = ScribbleOnDrop(format!("first"));
+    foo0 = Foo(0, &last_dropped); // OK
+    foo1 = Foo(1, &first_dropped);
+    //~^ ERROR `first_dropped` does not live long enough
+
+    println!("foo0.1: {:?} foo1.1: {:?}", foo0.1, foo1.1);
+}