diff --git a/ase/macros.h b/ase/macros.h
index 17fd6a63..8e54200c 100644
--- a/ase/macros.h
+++ b/ase/macros.h
@@ -1,5 +1,5 @@
 /*
- * $Id: macros.h,v 1.15 2005-03-30 10:21:33 bacon Exp $
+ * $Id: macros.h,v 1.16 2005-03-30 10:48:17 bacon Exp $
  */
 
 #ifndef _XP_MACROS_H_
@@ -24,12 +24,15 @@
     #define xp_main main
 #endif
 
-#define XP_TYPE_IS_SIGNED(type) (!(((type)0) < ((type)-1)))
+#define XP_TYPE_IS_SIGNED(type) (((type)0) > ((type)-1))
+#define XP_TYPE_IS_UNSIGNED(type) (((type)0) < ((type)-1))
 #define XP_TYPE_MAX(type) \
 	((XP_TYPE_IS_SIGNED(type)? (type)~((type)1 << (xp_sizeof(type) * 8 - 1)): (type)(~(type)0)))
 #define XP_TYPE_MIN(type) \
 	((XP_TYPE_IS_SIGNED(type)? (type)((type)1 << (xp_sizeof(type) * 8 - 1)): (type)0))
 
+#define XP_NUM_IS_POW2(x) (((x) & ((x) - 1)) == 0)
+
 #define XP_LOOP_CONTINUE(id) goto __loop_ ## id ## _begin__;
 #define XP_LOOP_BREAK(id)    goto __loop_ ## id ## _end__;
 #define XP_LOOP_BEGIN(id)    __loop_ ## id ## _begin__: {