diff --git a/src/allreduce.h b/src/allreduce.h
index 9f150dcf4..ef3fe589b 100644
--- a/src/allreduce.h
+++ b/src/allreduce.h
@@ -47,7 +47,7 @@ void Finalize(void) {
   engine::Finalize();
 }
 #ifdef TEST
-void SetMock(test::Mock& mock) {
+void SetMock(const test::Mock& mock) {
   engine::SetMock(mock);
 }
 #endif
diff --git a/src/engine.h b/src/engine.h
index 852e9187a..dc3a14049 100644
--- a/src/engine.h
+++ b/src/engine.h
@@ -82,7 +82,7 @@ void Finalize(void);
 IEngine *GetEngine(void);
 
 #ifdef TEST
-void SetMock(test::Mock& mock);
+void SetMock(const test::Mock& mock);
 #endif
 
 }  // namespace engine
diff --git a/src/engine_tcp.cpp b/src/engine_tcp.cpp
index e00b70f1c..c34d7d86b 100644
--- a/src/engine_tcp.cpp
+++ b/src/engine_tcp.cpp
@@ -42,7 +42,7 @@ class SyncManager : public IEngine {
   }
 
   #ifdef TEST
-  inline void SetMock(test::Mock& mock) {
+  inline void SetMock(const test::Mock& mock) {
     this->mock = mock;
   }
   #endif
@@ -501,7 +501,7 @@ void Init(int argc, char *argv[]) {
 
 #ifdef TEST
 /*! \brief sets a mock to the manager for testing purposes */
-void SetMock(test::Mock& mock) {
+void SetMock(const test::Mock& mock) {
   manager.SetMock(mock);
 }
 #endif
diff --git a/test/Makefile b/test/Makefile
index 78c6095e4..ef752de74 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -34,4 +34,4 @@ $(MPIBIN) :
 	$(MPICXX) $(CFLAGS) $(LDFLAGS) -o $@ $(filter %.cpp %.o %.c, $^)
 
 clean:
-	$(RM) $(BIN) $(MPIBIN) *~ ../src/*~
+	$(RM) $(OBJ) $(BIN) $(MPIBIN) *~ ../src/*~
diff --git a/test/test_allreduce.cpp b/test/test_allreduce.cpp
index 6da800f90..185d8ea6d 100644
--- a/test/test_allreduce.cpp
+++ b/test/test_allreduce.cpp
@@ -62,8 +62,8 @@ inline void TestBcast(size_t n, int root) {
   utils::Check(res == s, "[%d] TestBcast fail", rank);
 }
 
-// ugly stuff, just to see if it works
-inline void record(test::Mock& mock, int rank) {
+// ugly stuff, just to see if it works. To be removed
+inline void Record(test::Mock& mock, const int rank) {
   switch(rank) {
     case 0:
       mock.OnAllReduce(0, false);
@@ -77,12 +77,6 @@ inline void record(test::Mock& mock, int rank) {
   }
 }
 
-// to be removed, should be added in engine tcp
-inline void replay(test::Mock& mock, int rank) {
-  printf("[%d] All reduce %d\n", rank, mock.AllReduce(rank));
-  printf("[%d] All reduce %d\n", rank, mock.AllReduce(rank));
-}
-
 int main(int argc, char *argv[]) {
   if (argc < 2) {
     printf("Usage: <ndata>\n");
@@ -95,14 +89,11 @@ int main(int argc, char *argv[]) {
 
   #ifdef TEST
     test::Mock mock;
-    record(mock, rank);
+    Record(mock, rank);
     mock.Replay();
-    //replay(mock, rank);
     sync::SetMock(mock);
   #endif
 
-
-
   printf("[%d] start at %s\n", rank, name.c_str());
   TestMax(n);
   printf("[%d] TestMax pass\n", rank);