[haskell-llvm] dynamic linking

[Henning Thielemann]

I have build LLVM with debugging output and since this becomes rather big, 
I have only built the compiler target for my machine. This is no problem 
with static linking in Haskell, but with dynamic linking the linker 
complains about the missing shared object files of the target backends 
that I have not built.

llvm/example$ ghc -Wall -optl -w -dynamic --make -o Vector.dynexe -main-is Vector.main Vector.hs

/home/thielema/.cabal/lib/llvm-0.9.0.1/ghc-6.12.3/libHSllvm-0.9.0.1-ghc6.12.3.so: 
undefined reference to `LLVMInitializeSparcTarget'
/home/thielema/.cabal/lib/llvm-0.9.0.1/ghc-6.12.3/libHSllvm-0.9.0.1-ghc6.12.3.so: 
undefined reference to `LLVMInitializeMSILTarget'
/home/thielema/.cabal/lib/llvm-0.9.0.1/ghc-6.12.3/libHSllvm-0.9.0.1-ghc6.12.3.so: 
undefined reference to `LLVMInitializeMipsTargetInfo'
/home/thielema/.cabal/lib/llvm-0.9.0.1/ghc-6.12.3/libHSllvm-0.9.0.1-ghc6.12.3.so: 
undefined reference to `LLVMInitializeARMTarget'
/home/thielema/.cabal/lib/llvm-0.9.0.1/ghc-6.12.3/libHSllvm-0.9.0.1-ghc6.12.3.so: 
undefined reference to `LLVMInitializePIC16TargetInfo'
...


I have removed the according modules from the Other-Modules list in 
llvm.cabal and then I get cute small running executables! Now I wonder how 
the 'llvm' package could manage to automatically ignore non-existent 
backends? Is it possible to check at runtime which backends are available 
and load them on demand?