Good news for those shy to patch LLVM source code and build from scratch. The patch which adds GHC calling convention for ARM platform is merged for inclusion in LLVM 3.0 release. This is mainly due to David Terei persistence and constant push on Apple engineering to get it in since I’ve submitted the patch for inclusion just last day and was not able to answer all the questions arising from it. David not only replied with all needed information, but also kept emailing LLVM 3.0 release engineer and asking for inclusion. Thanks David!