diff --git a/gtsam/geometry/tests/testTriangulation.cpp b/gtsam/geometry/tests/testTriangulation.cpp
index 89b320e94..56f8e3db8 100644
--- a/gtsam/geometry/tests/testTriangulation.cpp
+++ b/gtsam/geometry/tests/testTriangulation.cpp
@@ -824,7 +824,7 @@ TEST(triangulation, reprojectionError_cameraComparison) {
       Point3(0.0, 0.0, 0.0));  // with z pointing along x axis of global frame
   Point3 landmarkL(5.0, 0.0, 0.0);  // 1m in front of poseA
   SphericalCamera sphericalCamera(poseA);
-  Unit3 u = sphericalCamera.project(landmarkL);
+  // TODO(dellaert): check Unit3 u = sphericalCamera.project(landmarkL);
 
   static Cal3_S2::shared_ptr sharedK(new Cal3_S2(60, 640, 480));
   PinholePose<Cal3_S2> pinholeCamera(poseA, sharedK);
diff --git a/gtsam/nonlinear/tests/testValues.cpp b/gtsam/nonlinear/tests/testValues.cpp
index 4f55027ba..a738ecc1d 100644
--- a/gtsam/nonlinear/tests/testValues.cpp
+++ b/gtsam/nonlinear/tests/testValues.cpp
@@ -188,15 +188,21 @@ TEST(Values, InsertOrAssign) {
 TEST(Values, basic_functions)
 {
   Values values;
-  const Values& values_c = values;
   Matrix23 M1 = Matrix23::Zero(), M2 = Matrix23::Zero();
   values.insert(2, Vector3(0, 0, 0));
   values.insert(4, Vector3(0, 0, 0));
   values.insert(6, M1);
   values.insert(8, M2);
 
+  EXPECT(!values.exists(1));
+  EXPECT(values.exists(2));
+  EXPECT(values.exists(4));
+  EXPECT(values.exists(6));
+  EXPECT(values.exists(8));
+
 #ifdef GTSAM_ALLOW_DEPRECATED_SINCE_V42
   // find
+  const Values& values_c = values;
   EXPECT_LONGS_EQUAL(4, values.find(4)->key);
   EXPECT_LONGS_EQUAL(4, values_c.find(4)->key);
 
diff --git a/gtsam/slam/InitializePose3.cpp b/gtsam/slam/InitializePose3.cpp
index e8ec9181c..75c33efa6 100644
--- a/gtsam/slam/InitializePose3.cpp
+++ b/gtsam/slam/InitializePose3.cpp
@@ -206,12 +206,11 @@ Values InitializePose3::computeOrientationsGradient(
   // Return correct rotations
   const Rot3& Rref = inverseRot.at(initialize::kAnchorKey); // This will be set to the identity as so far we included no prior
   Values estimateRot;
-    for (const auto key_R : inverseRot) {
+  for (const auto& key_R : inverseRot) {
     const Key& key = key_R.first;
-    const Rot3& Ri = key_R.second;
     if (key != initialize::kAnchorKey) {
-      const Rot3& R = inverseRot.at(key);
-      if(setRefFrame)
+      const Rot3& R = key_R.second;
+      if (setRefFrame)
         estimateRot.insert(key, Rref.compose(R.inverse()));
       else
         estimateRot.insert(key, R.inverse());
diff --git a/gtsam/slam/tests/testLago.cpp b/gtsam/slam/tests/testLago.cpp
index 5d429796d..fda39c169 100644
--- a/gtsam/slam/tests/testLago.cpp
+++ b/gtsam/slam/tests/testLago.cpp
@@ -283,7 +283,7 @@ TEST( Lago, largeGraphNoisy_orientations ) {
   Values::shared_ptr expected;
   boost::tie(gmatlab, expected) = readG2o(matlabFile);
 
-  for(const auto key_pose: expected->extract<Pose2>()){
+  for(const auto& key_pose: expected->extract<Pose2>()){
     const Key& k = key_pose.first;
     const Pose2& pose = key_pose.second;
     EXPECT(assert_equal(pose, actual.at<Pose2>(k), 1e-5));
@@ -310,7 +310,7 @@ TEST( Lago, largeGraphNoisy ) {
   Values::shared_ptr expected;
   boost::tie(gmatlab, expected) = readG2o(matlabFile);
 
-  for(const auto key_pose: expected->extract<Pose2>()){
+  for(const auto& key_pose: expected->extract<Pose2>()){
     const Key& k = key_pose.first;
     const Pose2& pose = key_pose.second;
     EXPECT(assert_equal(pose, actual.at<Pose2>(k), 1e-2));
diff --git a/timing/timeCameraExpression.cpp b/timing/timeCameraExpression.cpp
index 509294999..7a492822d 100644
--- a/timing/timeCameraExpression.cpp
+++ b/timing/timeCameraExpression.cpp
@@ -34,7 +34,7 @@ boost::shared_ptr<Cal3_S2> fixedK(new Cal3_S2());
 Point2 myProject(const Pose3& pose, const Point3& point,
     OptionalJacobian<2,6> H1, OptionalJacobian<2,3> H2) {
   PinholeCamera<Cal3_S2> camera(pose, *fixedK);
-  return camera.project(point, H1, H2, boost::none);
+  return camera.project(point, H1, H2, {});
 }
 
 int main() {
@@ -99,7 +99,6 @@ int main() {
   // ExpressionFactor, optimized
   // Oct 3, 2014, Macbook Air
   // 9.0 musecs/call
-  typedef PinholeCamera<Cal3_S2> Camera;
   NonlinearFactor::shared_ptr g3 =
       boost::make_shared<ExpressionFactor<Point2> >(model, z,
           Point2_(myProject, x, p));
diff --git a/timing/timePinholeCamera.cpp b/timing/timePinholeCamera.cpp
index 1578bb0a8..b865c82f7 100644
--- a/timing/timePinholeCamera.cpp
+++ b/timing/timePinholeCamera.cpp
@@ -84,7 +84,7 @@ int main()
     Matrix Dpose, Dpoint;
     long timeLog = clock();
     for(int i = 0; i < n; i++)
-      camera.project(point1, Dpose, Dpoint, boost::none);
+      camera.project(point1, Dpose, Dpoint, {});
     long timeLog2 = clock();
     double seconds = (double)(timeLog2-timeLog)/CLOCKS_PER_SEC;
     cout << ((double)seconds*1e9/n) << " nanosecs/call" << endl;