--- ./src/test/regress/pg_regress.c.orig	2020-08-10 23:15:53.000000000 +0200
+++ ./src/test/regress/pg_regress.c	2020-08-16 15:50:06.439293508 +0200
@@ -2408,6 +2408,7 @@
 		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 : "",