[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:
            Type:  bug               |                  Status:  infoneeded
        Priority:  normal            |               Milestone:  7.12.1
       Component:  Compiler          |                 Version:  7.6.3
      Resolution:                    |                Keywords:  testcase
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by nomeata):

 > and we use the interface hash to determine whether to write a new
 interface file,

 Ah, this is new to me. I assumed that when a module is compiled, its
 interface is written, and the interface hash is only used to decide
 whether to rebuild another module or not.

 But you are right, this deserves a separate ticket.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8144#comment:35>
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