diff --git a/qlo10k1/src/ld10k1file.cpp b/qlo10k1/src/ld10k1file.cpp
index 5742d61..c85e709 100644
--- a/qlo10k1/src/ld10k1file.cpp
+++ b/qlo10k1/src/ld10k1file.cpp
@@ -19,6 +19,7 @@
  *
  */
  
+#include <stdlib.h>
 #include "ld10k1file.h"
 
 class EMU10k1FilePrivate
diff --git a/qlo10k1/src/strglobal.cpp b/qlo10k1/src/strglobal.cpp
index b3b322c..e5bc7d9 100644
--- a/qlo10k1/src/strglobal.cpp
+++ b/qlo10k1/src/strglobal.cpp
@@ -19,6 +19,7 @@
  *
  */
  
+#include <stdlib.h>
 #include "strglobal.h"
 #include "strparam.h"
 #include "structure.h"
diff --git a/qlo10k1/src/strparam.cpp b/qlo10k1/src/strparam.cpp
index 9f0653d..b042d75 100644
--- a/qlo10k1/src/strparam.cpp
+++ b/qlo10k1/src/strparam.cpp
@@ -19,6 +19,7 @@
  *
  */
  
+#include <stdlib.h>
 #include <lo10k1/lo10k1.h>
 
 #include "strglobal.h"