diff --git a/reactos/lib/rosrtl/thread/stack.c b/reactos/lib/rosrtl/thread/stack.c
index 66c24766b24..d74ffdb9b77 100644
--- a/reactos/lib/rosrtl/thread/stack.c
+++ b/reactos/lib/rosrtl/thread/stack.c
@@ -7,10 +7,12 @@
 #include <ntos.h>
 
 #define NDEBUG
-#include <ntdll/ntdll.h>
+#include <debug.h>
 
 #include <rosrtl/thread.h>
 
+#define ROUNDUP(a,b)	((((a)+(b)-1)/(b))*(b))
+
 NTSTATUS NTAPI RtlRosCreateStack
 (
  IN HANDLE ProcessHandle,