Check that we have a working tar before trying to use it

Issue exposed by commit edc2332550 and the buildfarm.

Backpatch to release 14 where this usage started.

diff --git a/src/bin/pg_basebackup/t/010_pg_basebackup.pl b/src/bin/pg_basebackup/t/010_pg_basebackup.pl
index bde31b3c03d4c84b878e1fb325eedbd7bb910425..21c92fe60d30b88ed828915fb5e8fc2d689e2035 100644 (file)
--- a/src/bin/pg_basebackup/t/010_pg_basebackup.pl
+++ b/src/bin/pg_basebackup/t/010_pg_basebackup.pl
@@ -268,7 +268,8 @@ SKIP:
 {
    my $tar = $ENV{TAR};
    skip "no tar program available", 1
-     if (!defined $tar || $tar eq '');
+     if (!defined $tar || $tar eq ''
+         || system_log($tar, '--version') != 0);
 
    my $node2 = get_new_node('replica');