'backslash' build problems on windows

[Twan van Laarhoven]

I am having some problems with the latest builds of GHC on windows. For some 
reason ghc has decided to use backslashes in filenames. This leads to 
problems when building the stage libraries and the stage 2 compiler. I run 
the scripts from a mingw bash shell.

The following problems occur:
  - Warnings:
      .../ghc3228_0/ghc3228_0.lpp:1: warning: unknown escape sequence '\B'
    these are caused by the #line directive in the preprocessed file, 
something like
      #line 1 ".\basicTypes/BasicTypes.lhs"

  - When building the dependencies (in dist/build/.depend) become something 
like:
      dist/build\GHC/PrimopWrappers.o : .\GHC/PrimopWrappers.hs
    make then ignores these dependencies and tries to build the wrong files.

  - When testing, some unexpected failures occur, because the error message 
says ".\Something.hs" instead of "Something.hs".


The solution to all these problems is to use a '/' instead of a '\'. I 
suspect the problem was caused by the patch:
   Sat Jan 12 18:28:37 W. Europe Standard Time 2008  Ian Lynagh
    * FilePath fixes

Twan