Dear GHC team, I have compared for performance on DoCon of ghc-7.4.1 registerised and unregisterised, both made from source by ghc-7.4.1 (Debian Linux, GenuineIntel, Intel(R) Core(TM)2 CPU), DoCon and its test compiled under -O (-O2 is not better than -O). `registerised' is 5.4 times faster in building DoCon, is 3 times faster in running the DoCon test, produces 1.7 times smaller .a library file for DoCon. All right. Please, keep on supporting the portable (via-C) branch. Regards, ------ Sergei mechvel@botik.ru