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

[GHC]

#8144: Interface hashes include time stamp of dependent files (UsageFile mtime)
-------------------------------------+-------------------------------------
        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:
-------------------------------------+-------------------------------------

Comment (by rwbarton):

 nomeata, sorry if I am missing something obvious, but this ticket seems to
 be about the time stamp not appearing in the interface hash, so the fact
 that this ticket is just waiting for a test is not incompatible with the
 interface hash including the file name.

 Currently we need the .h file name in the interface file so that we can
 check whether the file fingerprint matches, and we use the interface hash
 to determine whether to write a new interface file, so it's not
 immediately obvious that we can avoid putting the file name in the
 interface hash. Maybe you'd like to create a new ticket about finding some
 way to avoid this?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8144#comment:34>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler