It looks like it has been like this for a couple of years. I guess this might have been found/fixed earlier had the code been compiled differently:
check.c: In function ‘check_for_new_tablespace_dir’: check.c:381:43: warning: declaration of ‘new_cluster’ shadows a global declaration [-Wshadow] check_for_new_tablespace_dir(ClusterInfo *new_cluster) ^ In file included from check.c:16:0: pg_upgrade.h:337:4: warning: shadowed declaration is here [-Wshadow] new_cluster; ^
~~~
PSA a small patch to remove the unnecessary parameter, and so eliminate this shadowing.
Thoughts?
------ Kind Regards, Peter Smith. Fujitsu Australia.