diff --git a/gtsam/base/Vector.cpp b/gtsam/base/Vector.cpp
index 6dc9800ca..7caf490ef 100644
--- a/gtsam/base/Vector.cpp
+++ b/gtsam/base/Vector.cpp
@@ -125,8 +125,8 @@ bool assert_inequal(const Vector& expected, const Vector& actual, double tol) {
 bool assert_equal(const SubVector& expected, const SubVector& actual, double tol) {
   if (equal_with_abs_tol(expected,actual,tol)) return true;
   cout << "not equal:" << endl;
-  print(expected, "expected");
-  print(actual, "actual");
+  print(static_cast<Vector>(expected), "expected");
+  print(static_cast<Vector>(actual), "actual");
   return false;
 }