diff --git a/test4/test4.hpp b/test4/test4.hpp
index e57f5e23..862bb058 100644
--- a/test4/test4.hpp
+++ b/test4/test4.hpp
@@ -43,7 +43,6 @@ void initialize_matrix (M &m) {
             m (i, j) = i * size1 + j + 1.f;
 }
 
-void test_vector ();
 void test_matrix_vector ();
 void test_matrix ();
 
diff --git a/test5/test5.hpp b/test5/test5.hpp
index 0cf465d2..6089ecab 100644
--- a/test5/test5.hpp
+++ b/test5/test5.hpp
@@ -60,7 +60,6 @@ void initialize_matrix (M &m) {
 }
 
 
-void test_vector ();
 void test_matrix_vector ();
 void test_matrix ();
 
diff --git a/test6/test6.hpp b/test6/test6.hpp
index e6bb5e88..40433177 100644
--- a/test6/test6.hpp
+++ b/test6/test6.hpp
@@ -60,7 +60,6 @@ void initialize_matrix (M &m) {
 }
 
 
-void test_vector ();
 void test_matrix_vector ();
 void test_matrix ();