[GHC] #8144: Interface hashes include time stamp of dependent files (UsageFile mtime)

[GHC]

#8144: Interface hashes include time stamp of dependent files (UsageFile mtime)
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        Reporter:  nh2                           |            Owner:  nh2
            Type:  bug                           |           Status:  patch
        Priority:  normal                        |        Milestone:
       Component:  Compiler                      |          Version:  7.6.3
      Resolution:                                |         Keywords:
Operating System:  Unknown/Multiple              |     Architecture:
 Type of failure:  Compile-time performance bug  |  Unknown/Multiple
       Test Case:                                |       Difficulty:
        Blocking:                                |  Unknown
                                                 |       Blocked By:
                                                 |  Related Tickets:
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Comment (by nh2):

 There is small bug in the replacement code used for the stage 1 compiler:
 The input file is never read :P

 (Doesn't become obvious until you try to backport my change to 7.6.)

 Please pull:

 https://github.com/nh2/ghc/compare/fix-interface-hashes-mtime

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8144#comment:16>
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