1 files changed, 23 insertions, 0 deletions
diff --git a/src/test/ui/nll/relate_tys/hr-fn-aau-eq-abu.rs b/src/test/ui/nll/relate_tys/hr-fn-aau-eq-abu.rs
new file mode 100644
index 000000000..92730341c
--- /dev/null
+++ b/src/test/ui/nll/relate_tys/hr-fn-aau-eq-abu.rs
@@ -0,0 +1,23 @@
+// Test an interesting corner case that ought to be legal (though the
+// current code actually gets it wrong, see below): a fn that takes
+// two arguments that are references with the same lifetime is in fact
+// equivalent to a fn that takes two references with distinct
+// lifetimes. This is true because the two functions can call one
+// another -- effectively, the single lifetime `'a` is just inferred
+// to be the intersection of the two distinct lifetimes.
+//
+// check-pass
+// compile-flags:-Zno-leak-check
+
+use std::cell::Cell;
+
+fn make_cell_aa() -> Cell<for<'a> fn(&'a u32, &'a u32)> {
+    panic!()
+}
+
+fn aa_eq_ab() {
+    let a: Cell<for<'a, 'b> fn(&'a u32, &'b u32)> = make_cell_aa();
+    drop(a);
+}
+
+fn main() { }