1 files changed, 25 insertions, 0 deletions

diff --git a/tests/ui/issues/issue-41742.rs b/tests/ui/issues/issue-41742.rs
new file mode 100644
index 000000000..afe311b4d
--- /dev/null
+++ b/tests/ui/issues/issue-41742.rs
@@ -0,0 +1,25 @@
+use std::ops::{Index, IndexMut};
+
+struct S;
+struct H;
+
+impl S {
+    fn f(&mut self) {}
+}
+
+impl Index<u32> for H {
+    type Output = S;
+    fn index(&self, index: u32) -> &S {
+        unimplemented!()
+    }
+}
+
+impl IndexMut<u32> for H {
+    fn index_mut(&mut self, index: u32) -> &mut S {
+        unimplemented!()
+    }
+}
+
+fn main() {
+    H["?"].f(); //~ ERROR mismatched types
+}