[GHC] #13375: ghc-pkg "cache is out of date" message breaks testsuite

[GHC]

#13375: ghc-pkg "cache is out of date" message breaks testsuite
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        Reporter:  bgamari           |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  highest           |            Milestone:  8.2.1
       Component:  ghc-pkg           |              Version:  8.0.1
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by marinelli):

 Is it still open?

 I've just tried listing and dumping packages with the both release
 candidate versions, obtaining the same result, e.g.:

 {{{
 $ ghc-pkg list
 WARNING: cache is out of date:
 /opt/apps/ghc/20170510-8.2.1-rc2-1/lib/ghc-8.2.0.20170507/package.conf.d/package.cache
 ghc will see an old view of this package db. Use 'ghc-pkg recache' to fix.
 /opt/apps/ghc/20170510-8.2.1-rc2-1/lib/ghc-8.2.0.20170507/package.conf.d
     Cabal-2.0.0.0
     array-0.5.1.2
 ---✂---
 }}}

 I am working with a Debian distribution (testing channel) on a btrfs file
 system, and I've used the x86_64-deb8 builds of GHC.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13375#comment:7>
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