to answer this question myself how the use of another gcc is specified with effect, I used the following options with the 'cabal install' call: --ghc-options="-pgmc e:/programme/ghc/mingw-gcc4/bin/gcc.exe -pgml e:/programme/ghc/mingw-gcc4/bin/gcc.exe" See http://www.haskell.org/ghc/docs/latest/html/users_guide/options-phases.html#... (searched in the wrong direction, too many trees...). Slightly tuned, this should be the way to go in all similar cases. One thing I haven't considered yet is if the '--with-ld' and '--with-gcc' options (if curious too, see logs in my previous mail - Subject "[Haskell-cafe] caba install with external gcc toolchain not the ghc-bundled one") only effect what gets written into the setup-config/package.conf file or what other effects these have. Greets Daniel