--- calcchecksum-1.6-pre1/calcchecksum/calcchecksum.cpp
+++ calcchecksum-1.6-pre1/calcchecksum/calcchecksum.cpp
@@ -34,6 +34,8 @@
 #include <kurldrag.h>
 #include <kiconloader.h>
 
+#include <cstdlib>
+
 #include "calcchecksum.h"
 #include "comparewndimpl.h"
 #include "err.h"
--- calcchecksum-1.6-pre1/calcchecksum/globalstuff.cpp
+++ calcchecksum-1.6-pre1/calcchecksum/globalstuff.cpp
@@ -11,7 +11,8 @@
 
 #include "globalstuff.h"
 
-#include <stdio.h>
+#include <cstring>
+#include <cstdio>
 #include <sys/stat.h>
 
 using std::string;