1 files changed, 51 insertions, 0 deletions
diff --git a/src/test/ui/regions/regions-fn-subtyping-return-static-fail.rs b/src/test/ui/regions/regions-fn-subtyping-return-static-fail.rs
new file mode 100644
index 000000000..539221b5a
--- /dev/null
+++ b/src/test/ui/regions/regions-fn-subtyping-return-static-fail.rs
@@ -0,0 +1,51 @@
+// In this fn, the type `F` is a function that takes a reference to a
+// struct and returns another reference with the same lifetime.
+//
+// Meanwhile, the bare fn `foo` takes a reference to a struct with
+// *ANY* lifetime and returns a reference with the 'static lifetime.
+// This can safely be considered to be an instance of `F` because all
+// lifetimes are sublifetimes of 'static.
+
+#![allow(dead_code)]
+#![allow(unused_variables)]
+
+struct S;
+
+// Given 'cx, return 'cx
+type F = for<'cx> fn(&'cx S) -> &'cx S;
+fn want_F(f: F) {}
+
+// Given anything, return 'static
+type G = for<'cx> fn(&'cx S) -> &'static S;
+fn want_G(f: G) {}
+
+// Should meet both.
+fn foo(x: &S) -> &'static S {
+    panic!()
+}
+
+// Should meet both.
+fn bar<'a, 'b>(x: &'a S) -> &'b S {
+    panic!()
+}
+
+// Meets F, but not G.
+fn baz(x: &S) -> &S {
+    panic!()
+}
+
+fn supply_F() {
+    want_F(foo);
+
+    want_F(bar);
+
+    want_F(baz);
+}
+
+fn supply_G() {
+    want_G(foo);
+    want_G(bar);
+    want_G(baz); //~ ERROR mismatched types
+}
+
+pub fn main() {}