[GHC] #5110: Refuse to build if no mk/build.mk is supplied

[GHC]

#5110: Refuse to build if no mk/build.mk is supplied
---------------------------------+------------------------------------------
    Reporter:  ezyang            |       Owner:                   
        Type:  feature request   |      Status:  new              
    Priority:  normal            |   Component:  Build System     
     Version:  7.1               |    Keywords:                   
    Testcase:                    |   Blockedby:                   
          Os:  Unknown/Multiple  |    Blocking:                   
Architecture:  Unknown/Multiple  |     Failure:  Documentation bug
---------------------------------+------------------------------------------
 A common thing that trips up people who are hacking on GHC for the first
 time is not knowing about the mk/build.mk file. Without it, GHC builds
 with all optimizations, and the process is very slow (on order of two
 hours.)

 It may be useful to have the build system to refuse to build without a
 mk/build.mk file present. While there is certainly potential for
 annoyance, we can mitigate this by distributing source distributions that
 have empty mk/build.mk files. Thus end-users won't be bothered, but users
 who do Git checkouts will be asked about it. The build process could also
 conditionalize on the presence of a .git directory.

 Validates would not be affected.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5110>
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