1 files changed, 6 insertions, 0 deletions

diff --git a/tests/ui/issues/issue-26812.rs b/tests/ui/issues/issue-26812.rs
new file mode 100644
index 00000000000..3391ea4b350
--- /dev/null
+++ b/tests/ui/issues/issue-26812.rs
@@ -0,0 +1,6 @@
+#![feature(default_type_parameter_fallback)]
+
+fn avg<T=T::Item>(_: T) {}
+//~^ ERROR generic parameters with a default cannot use forward declared identifiers
+
+fn main() {}