Use class RateCtl instead of struct. Class RateCtl is defined in ratectl.hh and used elsewhere in the code too. --- ./mpeg2enc/encoderparams.hh.orig 2014-07-21 16:50:46.000000000 +0200 +++ ./mpeg2enc/encoderparams.hh 2014-07-21 16:50:56.000000000 +0200 @@ -79,7 +79,7 @@ }; -struct RateCtl; +class RateCtl; class MPEG2EncOptions; class EncoderParams