[Yhc] Problems getting Yhc compiling on MacOS

[Mike Dodds]

I've been having trouble getting yhc (devel) to compile on MacOS. I'm 
using: ghc 6.4, and gcc 4.0.1

I'm getting the following message:

[...]
Skipping  Package          ( ./Package.hs, ./Package.o )
Skipping  Phase            ( ./Phase.hs, ./Phase.o )
Skipping  Front            ( ./Front.lhs, ./Front.o )
Skipping  Compile          ( ./Compile.lhs, ./Compile.o )
Skipping  Make             ( ./Make.lhs, ./Make.o )
Skipping  Main             ( Main.hs, Main.o )
Linking ...
make -C src/cpphs-1.0
ghc --make cpphs.hs -o ../../inst/bin/cpphs
IChasing modules from: cpphs.hs
Skipping  ParseLib         ( ./ParseLib.hs, ./ParseLib.o )
Skipping  HashDefine       ( ./HashDefine.hs, ./HashDefine.o )
Skipping  SymTab           ( ./SymTab.hs, ./SymTab.o )
Skipping  Position         ( ./Position.hs, ./Position.o )
Skipping  Tokenise         ( ./Tokenise.hs, ./Tokenise.o )
Skipping  ReadFirst        ( ./ReadFirst.hs, ./ReadFirst.o )
Skipping  CppIfdef         ( ./CppIfdef.hs, ./CppIfdef.o )
Skipping  MacroPass        ( ./MacroPass.hs, ./MacroPass.o )
Skipping  RunCpphs         ( ./RunCpphs.hs, ./RunCpphs.o )
Skipping  Main             ( cpphs.hs, cpphs.o )
Linking ...
make -C src/packages/yhc-base-1.0
export YHC_BASE_PATH=../../../inst ; ../../../inst/bin/yhc -d 
../../../inst/lib/yhc/packages/yhc-base/1.0/ -i 
../../../inst/lib/yhc/packages/yhc-base/1.0/ -c System/Exit.hs
yhc: Error: File not found, Data.Ratio
Looked in:
  ../../../inst/lib/yhc/packages/yhc-base/1.0

make[1]: *** 
[../../../inst/lib/yhc/packages/yhc-base/1.0//System/Exit.hi] Error 1
make: *** [yhc-base] Error 2