1 files changed, 9 insertions, 0 deletions
diff --git a/src/test/ui/feature-gates/feature-gate-concat_idents.rs b/src/test/ui/feature-gates/feature-gate-concat_idents.rs
new file mode 100644
index 000000000..68caf3d71
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-concat_idents.rs
@@ -0,0 +1,9 @@
+const XY_1: i32 = 10;
+
+fn main() {
+    const XY_2: i32 = 20;
+    let a = concat_idents!(X, Y_1); //~ ERROR `concat_idents` is not stable
+    let b = concat_idents!(X, Y_2); //~ ERROR `concat_idents` is not stable
+    assert_eq!(a, 10);
+    assert_eq!(b, 20);
+}