1 files changed, 42 insertions, 0 deletions
diff --git a/tests/ui/traits/trait-impl-overflow-with-where-clause-20413.rs b/tests/ui/traits/trait-impl-overflow-with-where-clause-20413.rs
new file mode 100644
index 00000000000..e8c27ff5cc8
--- /dev/null
+++ b/tests/ui/traits/trait-impl-overflow-with-where-clause-20413.rs
@@ -0,0 +1,42 @@
+// https://github.com/rust-lang/rust/issues/20413
+trait Foo {
+    fn answer(self);
+}
+
+struct NoData<T>;
+//~^ ERROR: parameter `T` is never used
+
+impl<T> Foo for T where NoData<T>: Foo {
+  //~^ ERROR: overflow evaluating the requirement
+  fn answer(self) {
+    let val: NoData<T> = NoData;
+  }
+}
+
+trait Bar {
+    fn answer(self);
+}
+
+trait Baz {
+    fn answer(self);
+}
+
+struct AlmostNoData<T>(Option<T>);
+
+struct EvenLessData<T>(Option<T>);
+
+impl<T> Bar for T where EvenLessData<T>: Baz {
+//~^ ERROR: overflow evaluating the requirement
+  fn answer(self) {
+    let val: EvenLessData<T> = EvenLessData(None);
+  }
+}
+
+impl<T> Baz for T where AlmostNoData<T>: Bar {
+//~^ ERROR: overflow evaluating the requirement
+  fn answer(self) {
+    let val: NoData<T> = AlmostNoData(None);
+  }
+}
+
+fn main() {}