[Varnish] #1787: Varnish fails to start because of unused subs in VCL and bug in Red Hat systemd service

[Varnish]

#1787: Varnish fails to start because of unused subs in VCL and bug in Red Hat
systemd service
---------------------------------+-----------------------
 Reporter:  anders               |       Type:  defect
   Status:  new                  |   Priority:  normal
Milestone:  Varnish 4.0 release  |  Component:  packaging
  Version:  4.0.3                |   Severity:  normal
 Keywords:  redhat               |
---------------------------------+-----------------------
 I have vcc_err_unref set to off in varnish.params:

 [root at no000010sapit0 ~]# grep ^DAE /etc/varnish/varnish.params
 DAEMON_OPTS="-p vcc_err_unref=off"

 But when I try to start Varnish it fails with unused subs:

 [root at no000010sapit0 ~]# service varnish start
 Redirecting to /bin/systemctl start  varnish.service
 Job for varnish.service failed. See 'systemctl status varnish.service' and
 'journalctl -xn' for details.
 [root at no000010sapit0 ~]# journalctl -xn | cat
 -- Logs begin at Sun 2015-09-06 15:40:04 CEST, end at Wed 2015-09-09
 09:35:22 CEST. --
 Sep 09 09:35:22 no000010sapit0.moller.local varnishd[19404]: Message from
 VCC-compiler:
 Sep 09 09:35:22 no000010sapit0.moller.local varnishd[19404]: Unused sub
 pass_if_gethead, defined:
 Sep 09 09:35:22 no000010sapit0.moller.local varnishd[19404]: ('input' Line
 48 Pos 5)
 Sep 09 09:35:22 no000010sapit0.moller.local varnishd[19404]: sub
 pass_if_gethead

 The problem is that /usr/lib/systemd/system/varnish.service has an
 ExecStartPre
 that does not use/consider $DAEMON_OPTS. It needs to, particularly for
 that vcc_err_unref=off setting.

-- 
Ticket URL: <https://www.varnish-cache.org/trac/ticket/1787>
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