diff --git a/w-stacking.h b/w-stacking.h
index 845e923562bb7444365462ba5ad3e92cff252863..8e6ebde73462087c68f7f14697b6392f62ad779d 100755
--- a/w-stacking.h
+++ b/w-stacking.h
@@ -37,7 +37,7 @@ void wstack(
 }
 #else 
 void wstack(
-     int,
+     long long unsigned,
      unsigned int,
      unsigned int,
      unsigned int,
@@ -50,8 +50,8 @@ void wstack(
      double,
      double,
      int,
-     int,
-     int,
+     long long unsigned,
+     long long unsigned,
      double*,
      int,
      int);