1 files changed, 9 insertions, 0 deletions
diff --git a/src/test/ui/borrowck/immut-function-arguments.rs b/src/test/ui/borrowck/immut-function-arguments.rs
new file mode 100644
index 000000000..242a33e82
--- /dev/null
+++ b/src/test/ui/borrowck/immut-function-arguments.rs
@@ -0,0 +1,9 @@
+fn f(y: Box<isize>) {
+    *y = 5; //~ ERROR cannot assign
+}
+
+fn g() {
+    let _frob = |q: Box<isize>| { *q = 2; }; //~ ERROR cannot assign
+}
+
+fn main() {}