1 files changed, 17 insertions, 0 deletions
diff --git a/tests/ui/associated-consts/defaults-cyclic-fail.rs b/tests/ui/associated-consts/defaults-cyclic-fail.rs
new file mode 100644
index 000000000..a1c6840a0
--- /dev/null
+++ b/tests/ui/associated-consts/defaults-cyclic-fail.rs
@@ -0,0 +1,17 @@
+// build-fail
+
+// Cyclic assoc. const defaults don't error unless *used*
+trait Tr {
+    const A: u8 = Self::B;
+    //~^ cycle detected when const-evaluating + checking `Tr::A`
+
+    const B: u8 = Self::A;
+}
+
+// This impl is *allowed* unless its assoc. consts are used
+impl Tr for () {}
+
+fn main() {
+    // This triggers the cycle error
+    assert_eq!(<() as Tr>::A, 0);
+}