1 files changed, 1 insertions, 0 deletions
diff --git a/lib.h b/lib.h
index 2cfb714a..f4e24ca6 100644
--- a/lib.h
+++ b/lib.h
@@ -62,6 +62,7 @@ typedef double_uintptr_t dbl_ucnum;
 #define NUM_MIN (INT_PTR_MIN/4)
 
 #define PTR_BIT (SIZEOF_PTR * CHAR_BIT)
+#define NUM_BIT (PTR_BIT - TAG_SHIFT)
 
 #ifdef __GNUC__
 #define NORETURN __attribute__((noreturn))