diff --git a/cbits/stack.c b/cbits/stack.c
--- a/cbits/stack.c
+++ b/cbits/stack.c
@@ -4,7 +4,7 @@
 int
 stack_grow(struct stack *st, size_t new_size)
 {
-	void *new_st;
+	void **new_st;
 
 	if (st->asize >= new_size)
 		return 0;
@@ -12,6 +12,9 @@
 	new_st = realloc(st->item, new_size * sizeof(void *));
 	if (new_st == NULL)
 		return -1;
+
+	memset(new_st + st->asize, 0x0,
+		(new_size - st->asize) * sizeof(void *));
 
 	st->item = new_st;
 	st->asize = new_size;
diff --git a/sundown.cabal b/sundown.cabal
--- a/sundown.cabal
+++ b/sundown.cabal
@@ -1,6 +1,6 @@
 Cabal-version:          >= 1.6
 Name:                   sundown
-Version:                0.2.2
+Version:                0.2.3
 Author:                 Francesco Mazzoli (f@mazzo.li)
 Maintainer:             Francesco Mazzoli (f@mazzo.li)
 Build-Type:             Simple