1 files changed, 35 insertions, 0 deletions
diff --git a/src/test/ui/const-generics/generic_const_exprs/unify-op-with-fn-call.rs b/src/test/ui/const-generics/generic_const_exprs/unify-op-with-fn-call.rs
new file mode 100644
index 000000000..c0404d35b
--- /dev/null
+++ b/src/test/ui/const-generics/generic_const_exprs/unify-op-with-fn-call.rs
@@ -0,0 +1,35 @@
+#![feature(generic_const_exprs, adt_const_params, const_trait_impl)]
+#![allow(incomplete_features)]
+
+// test `N + N` unifies with explicit function calls for non-builtin-types
+#[derive(PartialEq, Eq)]
+struct Foo(u8);
+
+impl const std::ops::Add for Foo {
+    type Output = Self;
+
+    fn add(self, rhs: Self) -> Self::Output {
+        self
+    }
+}
+
+struct Evaluatable<const N: Foo>;
+
+fn foo<const N: Foo>(a: Evaluatable<{ N + N }>) {
+    bar::<{ std::ops::Add::add(N, N) }>();
+}
+
+fn bar<const N: Foo>() {}
+
+// test that `N + N` unifies with explicit function calls for builin-types
+struct Evaluatable2<const N: usize>;
+
+fn foo2<const N: usize>(a: Evaluatable2<{ N + N }>) {
+    bar2::<{ std::ops::Add::add(N, N) }>();
+    //~^ error: unconstrained generic constant
+    // FIXME(generic_const_exprs) make this not an error
+}
+
+fn bar2<const N: usize>() {}
+
+fn main() {}