1 files changed, 24 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/basic/testOverwrittenArgumentsWithUndefined.js b/js/src/jit-test/tests/basic/testOverwrittenArgumentsWithUndefined.js
new file mode 100644
index 0000000000..5f899243b7
--- /dev/null
+++ b/js/src/jit-test/tests/basic/testOverwrittenArgumentsWithUndefined.js
@@ -0,0 +1,24 @@
+function f() {
+    var a = arguments;
+    eval("assertEq(arguments[0], 42)");
+    eval("assertEq(arguments, a)");
+    arguments = undefined;
+    eval("assertEq(arguments, undefined)");
+    arguments = a;
+    eval("assertEq(arguments[0], 42)");
+    eval("assertEq(arguments, a)");
+}
+f(42);
+
+function f(z) {
+    var a = arguments;
+    eval("assertEq(arguments[0], 42)");
+    eval("assertEq(arguments, a)");
+    arguments = undefined;
+    eval("assertEq(arguments, undefined)");
+    z = 17;
+    eval("assertEq(a[0], 17)");
+    a[0] = 'ponies';
+    eval("assertEq(z, 'ponies')");
+}
+f(42);