OSX 10.10, python 3.4.2 and coverage 3.7.1 via MacPort.
If I put coverage option to ./.coveragerc, it works. If I rename the config file and use --rcfile=renamed_file, then coverage ignores config file. If I point to non-existing rcfile, coverage still doesn't complain.
Looks like coverage only checks .coveragerc file in current dir and ignores --rcfile option.