diff --git a/mathmlps/main.cc b/mathmlps/main.cc
index b1a10b7..6d1f58e 100644
--- a/mathmlps/main.cc
+++ b/mathmlps/main.cc
@@ -23,6 +23,7 @@
 #include <config.h>
 
 #include <cassert>
+#include <cstring>
 #include <fstream>
 
 #include <popt.h>
diff --git a/mathmlsvg/SMS.cc b/mathmlsvg/SMS.cc
index d513e43..1f1f9d1 100644
--- a/mathmlsvg/SMS.cc
+++ b/mathmlsvg/SMS.cc
@@ -22,6 +22,7 @@
 
 #include <config.h>
 
+#include <cstring>
 #include <sstream>
 #include "defs.h"
 #include "AbstractLogger.hh"
diff --git a/mathmlsvg/main.cc b/mathmlsvg/main.cc
index ee031a8..fcc9f5c 100644
--- a/mathmlsvg/main.cc
+++ b/mathmlsvg/main.cc
@@ -23,6 +23,7 @@
 #include <config.h>
 
 #include <cassert>
+#include <cstring>
 #include <fstream>
 
 #include <popt.h>
diff --git a/src/backend/ps/T1_FontDataBase.cc b/src/backend/ps/T1_FontDataBase.cc
index c4299ba..538f18d 100644
--- a/src/backend/ps/T1_FontDataBase.cc
+++ b/src/backend/ps/T1_FontDataBase.cc
@@ -23,7 +23,7 @@
 #include <t1lib.h>
 #include <config.h>
 #include <map>
-#include <string>
+#include <cstring>
 #include <stdlib.h>
 #include <iostream>
 #include <list>
diff --git a/src/engine/mathml/mathVariantAux.cc b/src/engine/mathml/mathVariantAux.cc
index 7792ca5..92e4716 100644
--- a/src/engine/mathml/mathVariantAux.cc
+++ b/src/engine/mathml/mathVariantAux.cc
@@ -23,6 +23,7 @@
 #include <config.h>
 
 #include <cassert>
+#include <cstring>
 
 #include "mathVariantAux.hh"