FLAC >=1.1.3 changed its API, and current versions of ardour (such as 2.0.3) cannot compile against it. Emerge ardour always returns the following errors: /usr/lib/gcc/i686-pc-linux-gnu/4.2.0/../../../libsndfile.so: undefined reference to `FLAC__seekable_stream_encoder_set_seek_callback' /usr/lib/gcc/i686-pc-linux-gnu/4.2.0/../../../libsndfile.so: undefined reference to `FLAC__seekable_stream_encoder_process_interleaved' /usr/lib/gcc/i686-pc-linux-gnu/4.2.0/../../../libsndfile.so: undefined reference to `FLAC__seekable_stream_encoder_get_resolved_state_string' /usr/lib/gcc/i686-pc-linux-gnu/4.2.0/../../../libsndfile.so: undefined reference to `FLAC__seekable_stream_encoder_set_write_callback' ...etc. adding a check to see if latest versions of FLAC are installed - and halting emerge - would help avoid the problem until the folks at ardour re-write the code. Reproducible: Always Steps to Reproduce: 1. update FLAC to >=1.1.3 2. try to install/emerge/update ardour. 3. repeat Actual Results: emerge ardour fails. Expected Results: emerge ardour should not fail. instead, current versions of ardour ebuilds should stop the emerge if a recent version of FLAC is installed, with an instruction to mask the ebuild until a later version comes out.
Please run revdep-rebuild from gentoolkit, and re-emerge libsndfile.