[GHC] #7992: Wrong invocation of configure script in libffi and integer-gmp

[GHC]

#7992: Wrong invocation of configure script in libffi and integer-gmp
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    Reporter:  merijn            |       Owner:                     
        Type:  bug               |      Status:  patch              
    Priority:  normal            |   Milestone:                     
   Component:  Build System      |     Version:  7.7                
    Keywords:  patch             |          Os:  Unknown/Multiple   
Architecture:  Unknown/Multiple  |     Failure:  Building GHC failed
  Difficulty:  Unknown           |    Testcase:                     
   Blockedby:                    |    Blocking:                     
     Related:                    |  
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Comment(by merijn):

 This is not about the generated configure script, it's an upstream issue
 with the behaviour of autoconf. Autoconf tries to determine the location
 from which a configure script is run and then set paths based on that. Due
 to the behaviour I described, running configure without the ./ and another
 configure script *anywhere in your path* will lead autoconf to conclude
 that configure is being run from *within that directory on your path*.
 This of course leads it to refer to all sorts of wrong paths.

 This change makes autoconf decide to check the current working directory
 for the location of the configure script before it tries looking in your
 path, as a result it uses the correct directory even if there's another
 configure script in your path anywhere.

 The output of "make show VALUE=SHELL" should be irrelevant, but is:
 {{{
 make -r --no-print-directory -f ghc.mk show
 SHELL="/bin/sh"
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7992#comment:3>
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