On Mon, Jul 16, 2018 at 08:34:35AM +0000, PG Bug reporting form wrote:
> I was creating streaming slave using
> https://wiki.postgresql.org/wiki/Streaming_Replication WiKi
> 
> Now when I have moved some of my config files to another place to keep them
> in SVN and also log folders to another partition streaming initialisation
> produces warnings.
> 
> Not sure if they are safe as pg_clog will be empty ...

That's unsafe for pg_clog as this tracks the transaction commit status
based on the transaction ID.  Note that this is not a bug, a base backup
using the replication protocol allows only symlinks to be in pg_tblspc,
and pg_wal (pg_xlog for <= 9.6) is handled as a special case.
--
Michael