1 files changed, 33 insertions, 0 deletions

diff --git a/tests/ui/issues/issue-4252.rs b/tests/ui/issues/issue-4252.rs
new file mode 100644
index 00000000000..0d47a7f0c16
--- /dev/null
+++ b/tests/ui/issues/issue-4252.rs
@@ -0,0 +1,33 @@
+// run-pass
+trait X {
+    fn call<T: std::fmt::Debug>(&self, x: &T);
+    fn default_method<T: std::fmt::Debug>(&self, x: &T) {
+        println!("X::default_method {:?}", x);
+    }
+}
+
+#[derive(Debug)]
+struct Y(#[allow(unused_tuple_struct_fields)] isize);
+
+#[derive(Debug)]
+struct Z<T: X+std::fmt::Debug> {
+    x: T
+}
+
+impl X for Y {
+    fn call<T: std::fmt::Debug>(&self, x: &T) {
+        println!("X::call {:?} {:?}", self, x);
+    }
+}
+
+impl<T: X + std::fmt::Debug> Drop for Z<T> {
+    fn drop(&mut self) {
+        // These statements used to cause an ICE.
+        self.x.call(self);
+        self.x.default_method(self);
+    }
+}
+
+pub fn main() {
+    let _z = Z {x: Y(42)};
+}