Error while compiling Ardour2

Ok, I get the following:

libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_encoder_set_seek_callback' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_encoder_process_interleaved’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_encoder_get_resolved_state_string' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_encoder_set_write_callback’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_encoder_delete' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_process_single’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_decoder_set_client_data' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_get_decode_position’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_decoder_set_write_callback' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_set_error_callback’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_encoder_init' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__StreamDecoderErrorStatusString’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_encoder_set_client_data' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_set_metadata_callback’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_encoder_set_sample_rate' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_finish’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_decoder_set_eof_callback' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_init’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_decoder_set_length_callback' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_encoder_set_bits_per_sample’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_decoder_new' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_set_seek_callback’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_decoder_set_tell_callback' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_set_read_callback’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_encoder_set_channels' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_encoder_finish’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_decoder_seek_absolute' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_encoder_new’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_encoder_set_tell_callback' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_process_until_end_of_metadata’
libs/libsndfile/libsndfile-ardour.so: undefined reference to FLAC__seekable_stream_decoder_get_state' libs/libsndfile/libsndfile-ardour.so: undefined reference toFLAC__seekable_stream_decoder_delete’
collect2: ld returned 1 exit status

when i start scons. The strange thing is that 'till yesterday i was able to compile it. Then i made a scons install -c and recompiled and I get this. I have already recompiled libsndfile and now I don’t know what to do. Any hints?