--- a/macro.c	Mon Jun 10 18:40:26 2013 -0400
+++ b/macro.c	Mon Jun 10 18:49:36 2013 -0400
@@ -355,12 +355,16 @@
 
 	assert(hashmask == numbuckets - 1);
 	newmask = (hashmask << 1) | 1U;
-	tossbit = newmask && ~hashmask;
+	tossbit = newmask & ~hashmask;
 	hashmask = newmask;
 
 	for (i=0; i<numbuckets; i++) {
 		newbucket = NULL;
 		oldbucket = macroarrayarray_get(&macros, i);
+		if (oldbucket == NULL) {
+			macroarrayarray_set(&macros, numbuckets + i, NULL);
+			continue;
+		}
 		oldnum = macroarray_num(oldbucket);
 		for (j=0; j<oldnum; j++) {
 			m = macroarray_get(oldbucket, j);
@@ -374,8 +378,11 @@
 		}
 		for (j=k=0; j<oldnum; j++) {
 			m = macroarray_get(oldbucket, j);
-			if (m != NULL && k < j) {
-				macroarray_set(oldbucket, k++, m);
+			if (m != NULL) {
+				if (k < j) {
+					macroarray_set(oldbucket, k, m);
+				}
+				k++;
 			}
 		}
 		macroarray_setsize(oldbucket, k);