index-pack: work around false positive use of uninitialized variable

The base_name variable in this function is given a value if cmd.args
array is not empty (i.e., if we run the pack-objects command), and
the function returns when cmd.args is empty before hitting a call to
free(base_name) near the end of the function, so to a human reader,
it can be seen that the variable is not used uninitialized, but to a
semi-intelligent compiler it is not so clear.

Squelch a false positive by a meaningless NULL initialization.

Signed-off-by: Junio C Hamano <[email protected]>

Author: gitster

builtin/index-pack.c

@@ -1803,7 +1803,7 @@ static void repack_local_links(void)
 	struct strbuf line = STRBUF_INIT;
 	struct oidset_iter iter;
 	struct object_id *oid;
-	char *base_name;
+	char *base_name = NULL;
 
 	if (!oidset_size(&outgoing_links))
 		return;