diff --git a/gtsam/base/tests/testMatrix.cpp b/gtsam/base/tests/testMatrix.cpp
index a7c218705..7802f27e1 100644
--- a/gtsam/base/tests/testMatrix.cpp
+++ b/gtsam/base/tests/testMatrix.cpp
@@ -173,7 +173,7 @@ TEST(Matrix, stack )
 {
   Matrix A = (Matrix(2, 2) << -5.0, 3.0, 00.0, -5.0).finished();
   Matrix B = (Matrix(3, 2) << -0.5, 2.1, 1.1, 3.4, 2.6, 7.1).finished();
-  Matrix AB = stack(2, &A, &B);
+  Matrix AB = gtsam::stack(2, &A, &B);
   Matrix C(5, 2);
   for (int i = 0; i < 2; i++)
     for (int j = 0; j < 2; j++)
@@ -187,7 +187,7 @@ TEST(Matrix, stack )
   std::vector<gtsam::Matrix> matrices;
   matrices.push_back(A);
   matrices.push_back(B);
-  Matrix AB2 = stack(matrices);
+  Matrix AB2 = gtsam::stack(matrices);
   EQUALITY(C,AB2);
 }
 
diff --git a/gtsam/linear/GaussianFactorGraph.cpp b/gtsam/linear/GaussianFactorGraph.cpp
index 664aeff6d..72eb107d0 100644
--- a/gtsam/linear/GaussianFactorGraph.cpp
+++ b/gtsam/linear/GaussianFactorGraph.cpp
@@ -379,7 +379,7 @@ namespace gtsam {
 
     gttic(Compute_minimizing_step_size);
     // Compute minimizing step size
-    double step = -gradientSqNorm / dot(Rg, Rg);
+    double step = -gradientSqNorm / gtsam::dot(Rg, Rg);
     gttoc(Compute_minimizing_step_size);
 
     gttic(Compute_point);