diff --git a/Source/cmXMLParser.cxx b/Source/cmXMLParser.cxx
index 82be503cb..bc3ed6c13 100644
--- a/Source/cmXMLParser.cxx
+++ b/Source/cmXMLParser.cxx
@@ -17,6 +17,7 @@
 #include "cmXMLParser.h"
 
 #include <cmexpat/expat.h>
+#include <ctype.h>
 
 //----------------------------------------------------------------------------
 cmXMLParser::cmXMLParser()
diff --git a/Utilities/cmexpat/xmlparse.c b/Utilities/cmexpat/xmlparse.c
index 59543d379..0c84f221f 100644
--- a/Utilities/cmexpat/xmlparse.c
+++ b/Utilities/cmexpat/xmlparse.c
@@ -4,7 +4,7 @@ See the file COPYING for copying permission.
 */
 
 #include <cmexpat/expatConfig.h>
-#include "expat.h"
+#include <cmexpat/expat.h>
 
 #include <stddef.h>
 #include <string.h>