1 files changed, 22 insertions, 0 deletions
diff --git a/tests/ui/nll/issue-47470.rs b/tests/ui/nll/issue-47470.rs
new file mode 100644
index 000000000..72ee7f886
--- /dev/null
+++ b/tests/ui/nll/issue-47470.rs
@@ -0,0 +1,22 @@
+// Regression test for #47470: cached results of projections were
+// causing region relations not to be enforced at all the places where
+// they have to be enforced.
+
+struct Foo<'a>(&'a ());
+trait Bar {
+    type Assoc;
+    fn get(self) -> Self::Assoc;
+}
+
+impl<'a> Bar for Foo<'a> {
+    type Assoc = &'a u32;
+    fn get(self) -> Self::Assoc {
+        let local = 42;
+        &local //~ ERROR cannot return reference to local variable `local`
+    }
+}
+
+fn main() {
+    let f = Foo(&()).get();
+    println!("{}", f);
+}