Index: src/utils/tabcomplete.c
===================================================================
--- src/utils/tabcomplete.c	(revision 4983)
+++ src/utils/tabcomplete.c	(working copy)
@@ -196,7 +196,7 @@
 	 if (size == 0)
 		 return NULL;
 
-	 r = calloc(size + i*2, 1);
+	 r = calloc(size + i*2 + 1, 1);
 	 for (i = 0; list[i] != NULL; i++)
 	 {
 		 if ((casesensitive && strncmp(text, list[i], string_length) == 0)
@@ -381,7 +381,7 @@
 			 size += strlen(words_after_create[i].name);
 	 }
 
-	 r = calloc(size + i*2, 1);
+	 r = calloc(size + i*2 + 1, 1);
 	 for (i = 0; words_after_create[i].name != NULL; i++)
 	 {
 		 if (pg_strncasecmp(text, words_after_create[i].name, string_length) == 0)