[GHC] #16100: T11627a fails sometimes on CI

[GHC]

#16100: T11627a fails sometimes on CI
-------------------------------------+-------------------------------------
        Reporter:  mpickering        |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 I've also observed this `T11627a` failure on `validate-x86_64-darwin`
 ([https://ghc-
 gitlab.s3.amazonaws.com/6b/86/6b86b273ff34fce19d6b804eff5a3f5747ada4eaa22f1d49c01e52ddb7875b4b/2019_02_13/27060/42255/job.log
 ?response-content-type=text/plain%3B%20charset%3Dutf-8&response-content-
 disposition=inline&X-Amz-Expires=600&X-Amz-Date=20190213T104114Z&X-Amz-
 Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAI3NPPHETCY4XXTOA/20190213
 /us-east-1/s3/aws4_request&X-Amz-SignedHeaders=host&X-Amz-
 Signature=f7c384c7f84acb2c560f0243f14ac260daaf603a6686e676626e0a347bd55623
 example]).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16100#comment:3>
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