diff --git a/gtsam/basis/tests/testChebyshev.cpp b/gtsam/basis/tests/testChebyshev.cpp
index 64c925886..7d7f9323d 100644
--- a/gtsam/basis/tests/testChebyshev.cpp
+++ b/gtsam/basis/tests/testChebyshev.cpp
@@ -25,9 +25,10 @@
 using namespace std;
 using namespace gtsam;
 
+namespace {
 auto model = noiseModel::Unit::Create(1);
-
 const size_t N = 3;
+}  // namespace
 
 //******************************************************************************
 TEST(Chebyshev, Chebyshev1) {
diff --git a/gtsam/basis/tests/testChebyshev2.cpp b/gtsam/basis/tests/testChebyshev2.cpp
index 4cee70daf..6fafc0ccf 100644
--- a/gtsam/basis/tests/testChebyshev2.cpp
+++ b/gtsam/basis/tests/testChebyshev2.cpp
@@ -27,9 +27,11 @@ using namespace std;
 using namespace gtsam;
 using namespace boost::placeholders;
 
+namespace {
 noiseModel::Diagonal::shared_ptr model = noiseModel::Unit::Create(1);
 
 const size_t N = 32;
+}  // namespace
 
 //******************************************************************************
 TEST(Chebyshev2, Point) {