[GHC] #8591: Concurrent executions of ghc-pkg can cause inconstant package.cache files

[GHC]

#8591: Concurrent executions of ghc-pkg can cause inconstant package.cache files
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              Reporter:  janm        |            Owner:  pgj
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Package     |          Version:  7.6.3
  system                             |         Keywords:  ghc-pkg race
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:  FreeBSD     |       Difficulty:  Unknown
       Type of failure:  Other       |       Blocked By:
             Test Case:              |  Related Tickets:
              Blocking:              |
Differential Revisions:              |
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Comment (by pgj):

 Replying to [comment:5 janm]:
 > I am running a test  build now but code inspection shows that the same
 race is present. I expect it to fail.

 All right, excellent, thanks.

 > I also see that the FreeBSD port for lang/ghc limits concurrency to 4
 jobs, added in SVN rev 348842. Assuming you're also pgj at freebsd you
 committed the change, so probably know! This was in response to FreeBSD
 bug ports/186829.

 Well, to be honest, I did not realize that it was a related issue.  In the
 past, the GHC build system already had problems with parallel builds on
 FreeBSD due to e.g. low-resolution timestamps in the file system.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8591#comment:8>
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