/usr/include/gnuradio/trellis/ is in gnuradio-dev 3.7.9.1-2ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/gnuradio/trellis/api.h
/usr/include/gnuradio/trellis/base.h
/usr/include/gnuradio/trellis/calc_metric.h
/usr/include/gnuradio/trellis/constellation_metrics_cf.h
/usr/include/gnuradio/trellis/core_algorithms.h
/usr/include/gnuradio/trellis/encoder_bb.h
/usr/include/gnuradio/trellis/encoder_bi.h
/usr/include/gnuradio/trellis/encoder_bs.h
/usr/include/gnuradio/trellis/encoder_ii.h
/usr/include/gnuradio/trellis/encoder_si.h
/usr/include/gnuradio/trellis/encoder_ss.h
/usr/include/gnuradio/trellis/fsm.h
/usr/include/gnuradio/trellis/interleaver.h
/usr/include/gnuradio/trellis/metrics_c.h
/usr/include/gnuradio/trellis/metrics_f.h
/usr/include/gnuradio/trellis/metrics_i.h
/usr/include/gnuradio/trellis/metrics_s.h
/usr/include/gnuradio/trellis/pccc_decoder_b.h
/usr/include/gnuradio/trellis/pccc_decoder_combined_cb.h
/usr/include/gnuradio/trellis/pccc_decoder_combined_ci.h
/usr/include/gnuradio/trellis/pccc_decoder_combined_cs.h
/usr/include/gnuradio/trellis/pccc_decoder_combined_fb.h
/usr/include/gnuradio/trellis/pccc_decoder_combined_fi.h
/usr/include/gnuradio/trellis/pccc_decoder_combined_fs.h
/usr/include/gnuradio/trellis/pccc_decoder_i.h
/usr/include/gnuradio/trellis/pccc_decoder_s.h
/usr/include/gnuradio/trellis/pccc_encoder_bb.h
/usr/include/gnuradio/trellis/pccc_encoder_bi.h
/usr/include/gnuradio/trellis/pccc_encoder_bs.h
/usr/include/gnuradio/trellis/pccc_encoder_ii.h
/usr/include/gnuradio/trellis/pccc_encoder_si.h
/usr/include/gnuradio/trellis/pccc_encoder_ss.h
/usr/include/gnuradio/trellis/permutation.h
/usr/include/gnuradio/trellis/quicksort_index.h
/usr/include/gnuradio/trellis/sccc_decoder_b.h
/usr/include/gnuradio/trellis/sccc_decoder_combined_cb.h
/usr/include/gnuradio/trellis/sccc_decoder_combined_ci.h
/usr/include/gnuradio/trellis/sccc_decoder_combined_cs.h
/usr/include/gnuradio/trellis/sccc_decoder_combined_fb.h
/usr/include/gnuradio/trellis/sccc_decoder_combined_fi.h
/usr/include/gnuradio/trellis/sccc_decoder_combined_fs.h
/usr/include/gnuradio/trellis/sccc_decoder_i.h
/usr/include/gnuradio/trellis/sccc_decoder_s.h
/usr/include/gnuradio/trellis/sccc_encoder_bb.h
/usr/include/gnuradio/trellis/sccc_encoder_bi.h
/usr/include/gnuradio/trellis/sccc_encoder_bs.h
/usr/include/gnuradio/trellis/sccc_encoder_ii.h
/usr/include/gnuradio/trellis/sccc_encoder_si.h
/usr/include/gnuradio/trellis/sccc_encoder_ss.h
/usr/include/gnuradio/trellis/siso_combined_f.h
/usr/include/gnuradio/trellis/siso_f.h
/usr/include/gnuradio/trellis/siso_type.h
/usr/include/gnuradio/trellis/viterbi_b.h
/usr/include/gnuradio/trellis/viterbi_combined_cb.h
/usr/include/gnuradio/trellis/viterbi_combined_ci.h
/usr/include/gnuradio/trellis/viterbi_combined_cs.h
/usr/include/gnuradio/trellis/viterbi_combined_fb.h
/usr/include/gnuradio/trellis/viterbi_combined_fi.h
/usr/include/gnuradio/trellis/viterbi_combined_fs.h
/usr/include/gnuradio/trellis/viterbi_combined_ib.h
/usr/include/gnuradio/trellis/viterbi_combined_ii.h
/usr/include/gnuradio/trellis/viterbi_combined_is.h
/usr/include/gnuradio/trellis/viterbi_combined_sb.h
/usr/include/gnuradio/trellis/viterbi_combined_si.h
/usr/include/gnuradio/trellis/viterbi_combined_ss.h
/usr/include/gnuradio/trellis/viterbi_i.h
/usr/include/gnuradio/trellis/viterbi_s.h