[GHC] #8493: Can't compile happy + ghc with clang's CPP

[GHC]

#8493: Can't compile happy + ghc with clang's CPP
----------------------------------------+----------------------------------
        Reporter:  maxs                 |            Owner:
            Type:  bug                  |           Status:  new
        Priority:  highest              |        Milestone:  7.8.1
       Component:  libraries (other)    |          Version:  7.7
      Resolution:                       |         Keywords:  happy
Operating System:  MacOS X              |     Architecture:
 Type of failure:  Building GHC failed  |  Unknown/Multiple
       Test Case:                       |       Difficulty:  Unknown
        Blocking:                       |       Blocked By:
                                        |  Related Tickets:
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Comment (by maxs):

 Replying to [comment:2 hvr]:
 > Do I understand you right, that Clang's CPP converts spaces into tabs?
 :-/

 So this is what I thought 3 hours ago, I'm not so certain anymore.

 I'm trying to build happy (from git, 2cfc3b70cd from
 https://github.com/simonmar/happy)

 If I run:
 {{{
 ghc-7.6.3 -E -cpp templates/GenericTemplate.hs -DHAPPY_ARRAY
 }}}
 Then it has no tabs.

 But when I use cabal install instead, the file:

 {{{
 dist/build/happy/happy-tmp/AttrGrammerParser.hs
 }}}

 contains tabs.

 cabal builds it with:

 {{{
 '/usr/local/bin/clang-xcode5-wrapper' '-E' '-undef' '-traditional' '-m64'
 '-fno-stack-protector' '-m64' '-I' 'dist/build/happy/happy-tmp' '-I'
 'dist/build/happy/happy-tmp' '-I' 'dist/build/autogen' '-I'
 'dist/build/happy/happy-tmp' '-I'
 '/usr/local/Cellar/ghc/7.6.3/lib/ghc-7.6.3/base-4.6.0.1/include' '-I'
 '/usr/local/Cellar/ghc/7.6.3/lib/ghc-7.6.3/include'
 '-D__GLASGOW_HASKELL__=706' '-Ddarwin_BUILD_OS=1' '-Dx86_64_BUILD_ARCH=1'
 '-Ddarwin_HOST_OS=1' '-Dx86_64_HOST_ARCH=1' '-U __PIC__' '-D__PIC__'
 '-include' 'dist/build/autogen/cabal_macros.h' '-x' 'c' 'dist/build/happy
 /happy-tmp/AttrGrammarParser.hs' '-o'
 '/var/folders/4q/5j7w6x5x3c1bc427tcgvg4sc0000gn/T/ghc10733_0/ghc10733_6.hscpp'
 }}}

 where the wrapper is: https://github.com/ghc-ios/ghc-ios-
 scripts/blob/master/clang-xcode5-wrapper.hs

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8493#comment:3>
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