diff --git a/modules/seq/alg/src/entropy.cc b/modules/seq/alg/src/entropy.cc
index 7881512578187af9a0439ffe1ef44d5bab46dfe9..ed4f091d64678dc763b561f208873dd6795e4e85 100644
--- a/modules/seq/alg/src/entropy.cc
+++ b/modules/seq/alg/src/entropy.cc
@@ -17,7 +17,7 @@
 // 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 //------------------------------------------------------------------------------
 #include <limits> 
-
+#include <cstring>
 #include "entropy.hh"
 
 #include <ost/seq/aligned_column.hh>