1 files changed, 37 insertions, 0 deletions
diff --git a/tests/ui/polymorphization/const_parameters/functions.rs b/tests/ui/polymorphization/const_parameters/functions.rs
new file mode 100644
index 000000000..cbc1b63fb
--- /dev/null
+++ b/tests/ui/polymorphization/const_parameters/functions.rs
@@ -0,0 +1,37 @@
+// build-fail
+// compile-flags:-Zpolymorphize=on
+#![feature(generic_const_exprs, rustc_attrs)]
+//~^ WARN the feature `generic_const_exprs` is incomplete
+
+// This test checks that the polymorphization analysis correctly detects unused const
+// parameters in functions.
+
+// Function doesn't have any generic parameters to be unused.
+#[rustc_polymorphize_error]
+pub fn no_parameters() {}
+
+// Function has an unused generic parameter.
+#[rustc_polymorphize_error]
+pub fn unused<const T: usize>() {
+    //~^ ERROR item has unused generic parameters
+}
+
+// Function uses generic parameter in value of a binding.
+#[rustc_polymorphize_error]
+pub fn used_binding<const T: usize>() -> usize {
+    let x: usize = T;
+    x
+}
+
+// Function uses generic parameter in substitutions to another function.
+#[rustc_polymorphize_error]
+pub fn used_substs<const T: usize>() {
+    unused::<T>()
+}
+
+fn main() {
+    no_parameters();
+    unused::<1>();
+    used_binding::<1>();
+    used_substs::<1>();
+}