Reverse part of my previous changes
diff --git a/libbb/unarchive.c b/libbb/unarchive.c
index a17f7af..067e78b 100644
--- a/libbb/unarchive.c
+++ b/libbb/unarchive.c
@@ -538,7 +538,8 @@
 	int gunzip_pid;
 
 	if (filename == NULL) {
-		file_list = NULL;
+		file_list = xmalloc(sizeof(char *));
+		file_list[0] = NULL;
 	} else {
 		file_list = xmalloc(sizeof(char *) * 3);
 		file_list[0] = xstrdup(filename);