diff --git a/include/sdsl/int_vector_buffer.hpp b/include/sdsl/int_vector_buffer.hpp
index 288fce1dd..c09da33cd 100644
--- a/include/sdsl/int_vector_buffer.hpp
+++ b/include/sdsl/int_vector_buffer.hpp
@@ -544,7 +544,7 @@ class int_vector_buffer
                     return it += i;
                 }
 
-                iterator& operator-(difference_type i) const
+                iterator operator-(difference_type i) const
                 {
                     iterator it = *this;
                     return it -= i;