diff --git a/magick/xml-tree.c b/magick/xml-tree.c
index a9b6fd9..169f382 100644
--- a/magick/xml-tree.c
+++ b/magick/xml-tree.c
@@ -55,6 +55,7 @@
#include "magick/memory_.h"
#include "magick/semaphore.h"
#include "magick/string_.h"
+#include "magick/string-private.h"
#include "magick/xml-tree.h"
#include "magick/utility.h"
@@ -244,7 +245,7 @@
node=child;
if (node == (XMLTreeInfo *) NULL)
break;
- for (j=atol(subnode)-1; j > 0; j--)
+ for (j=StringToLong(subnode)-1; j > 0; j--)
{
node=GetXMLTreeOrdered(node);
if (node == (XMLTreeInfo *) NULL)
@@ -875,7 +876,7 @@
node=GetXMLTreeChild(node,tag);
if (node == (XMLTreeInfo *) NULL)
break;
- for (j=atol(subnode)-1; j > 0; j--)
+ for (j=StringToLong(subnode)-1; j > 0; j--)
{
node=GetXMLTreeOrdered(node);
if (node == (XMLTreeInfo *) NULL)