diff -ur postgresql-14.0.orig/src/test/regress/pg_regress.c postgresql-14.0/src/test/regress/pg_regress.c
--- postgresql-14.0.orig/src/test/regress/pg_regress.c	2021-11-01 14:50:12.561429947 +0100
+++ postgresql-14.0/src/test/regress/pg_regress.c	2021-11-01 14:50:27.681468493 +0100
@@ -2482,6 +2482,7 @@
 		header(_("starting postmaster"));
 		snprintf(buf, sizeof(buf),
 				 "\"%s%spostgres\" -D \"%s/data\" -F%s "
+				 "-c \"log_directory=log\" "
 				 "-c \"listen_addresses=%s\" -k \"%s\" "
 				 "> \"%s/log/postmaster.log\" 2>&1",
 				 bindir ? bindir : "",