This is a long standing omission, discovered when trying to write code
that relied on it.
Backpatch to all live branches.
$cfg .= ' --with-tcl' if ($self->{options}->{tcl});
$cfg .= ' --with-perl' if ($self->{options}->{perl});
$cfg .= ' --with-python' if ($self->{options}->{python});
+ my $port = $self->{options}->{'--with-pgport'};
+ $cfg .= " --with-pgport=$port" if defined($port)
return $cfg;
}