How can I specify which LLVM binaries GHC should use?

I have successfully built PortFusion with the brand new 64-bit GHC 7.6.1 Release Candidate 1 for Windows.

Using freshly downloaded native 64-bit mingw binaries from http://www.drangon.org/mingw, the network package was as easy to install (after a bunch of non-relevant small fixes) as a simple

CC=mingw64/bin/gcc cabal install

There is also an LLVM toolchain package on the same website.

Now I wonder how I could tell GHC to use specific LLVM binaries during compilation.

Would it be something as simple and similar to above as:

#v??v
 LLVM=????????? ghc -W -O2 -fllvm -optlo-O3 --make src/Main.hs
 LLVM=????????? cabal install PortFusion -f llvm #¹
#^??^

¹ relevant line in PortFusion.cabal defining the llvm flag

or completely different?