diff --git a/src/test/rustdoc/const-generics/const-generic-defaults.rs b/src/test/rustdoc/const-generics/const-generic-defaults.rs
new file mode 100644
index 00000000000..efe35bf7aa4
--- /dev/null
+++ b/src/test/rustdoc/const-generics/const-generic-defaults.rs
@@ -0,0 +1,6 @@
+#![crate_name = "foo"]
+#![feature(const_generics_defaults)]
+
+// @has foo/struct.Foo.html '//pre[@class="rust struct"]' \
+//      'pub struct Foo<const M: usize = 10_usize, const N: usize = M, T = i32>(_);'
+pub struct Foo<const M: usize = 10, const N: usize = M, T = i32>(T);