Registration problems:
  symbol ‘`_dplyr_anti_join_impl`’ not in namespace:
   .Call(`_dplyr_anti_join_impl`, x, y, by_x, by_y, na_match)
  symbol ‘`_dplyr_arrange_impl`’ not in namespace:
   .Call(`_dplyr_arrange_impl`, data, quosures)
  symbol ‘`_dplyr_as_regular_df`’ not in namespace:
   .Call(`_dplyr_as_regular_df`, df)
  symbol ‘`_dplyr_assert_all_white_list`’ not in namespace:
   .Call(`_dplyr_assert_all_white_list`, data)
  symbol ‘`_dplyr_between`’ not in namespace:
   .Call(`_dplyr_between`, x, left, right)
  symbol ‘`_dplyr_bind_rows_`’ not in namespace:
   .Call(`_dplyr_bind_rows_`, dots, id)
  symbol ‘`_dplyr_cbind_all`’ not in namespace:
   .Call(`_dplyr_cbind_all`, dots)
  symbol ‘`_dplyr_combine_all`’ not in namespace:
   .Call(`_dplyr_combine_all`, data)
  symbol ‘`_dplyr_combine_vars`’ not in namespace:
   .Call(`_dplyr_combine_vars`, vars, xs)
  symbol ‘`_dplyr_compatible_data_frame`’ not in namespace:
   .Call(`_dplyr_compatible_data_frame`, x, y, ignore_col_order, 
       convert)
  symbol ‘`_dplyr_compatible_data_frame_nonames`’ not in namespace:
   .Call(`_dplyr_compatible_data_frame_nonames`, x, y, convert)
  symbol ‘`_dplyr_cumall`’ not in namespace:
   .Call(`_dplyr_cumall`, x)
  symbol ‘`_dplyr_cumany`’ not in namespace:
   .Call(`_dplyr_cumany`, x)
  symbol ‘`_dplyr_cummean`’ not in namespace:
   .Call(`_dplyr_cummean`, x)
  symbol ‘`_dplyr_dfloc`’ not in namespace:
   .Call(`_dplyr_dfloc`, df)
  symbol ‘`_dplyr_distinct_impl`’ not in namespace:
   .Call(`_dplyr_distinct_impl`, df, vars, keep)
  symbol ‘`_dplyr_equal_data_frame`’ not in namespace:
   .Call(`_dplyr_equal_data_frame`, x, y, ignore_col_order, ignore_row_order, 
       convert)
  symbol ‘`_dplyr_filter_impl`’ not in namespace:
   .Call(`_dplyr_filter_impl`, df, quo)
  symbol ‘`_dplyr_flatten_bindable`’ not in namespace:
   .Call(`_dplyr_flatten_bindable`, x)
  symbol ‘`_dplyr_full_join_impl`’ not in namespace:
   .Call(`_dplyr_full_join_impl`, x, y, by_x, by_y, suffix_x, suffix_y, 
       na_match)
  symbol ‘`_dplyr_gp`’ not in namespace:
   .Call(`_dplyr_gp`, x)
  symbol ‘`_dplyr_group_size_grouped_cpp`’ not in namespace:
   .Call(`_dplyr_group_size_grouped_cpp`, gdf)
  symbol ‘`_dplyr_grouped_df_impl`’ not in namespace:
   .Call(`_dplyr_grouped_df_impl`, data, symbols, drop)
  symbol ‘`_dplyr_grouped_indices_grouped_df_impl`’ not in namespace:
   .Call(`_dplyr_grouped_indices_grouped_df_impl`, gdf)
  symbol ‘`_dplyr_init_logging`’ not in namespace:
   .Call(`_dplyr_init_logging`, log_level)
  symbol ‘`_dplyr_inner_join_impl`’ not in namespace:
   .Call(`_dplyr_inner_join_impl`, x, y, by_x, by_y, suffix_x, suffix_y, 
       na_match)
  symbol ‘`_dplyr_intersect_data_frame`’ not in namespace:
   .Call(`_dplyr_intersect_data_frame`, x, y)
  symbol ‘`_dplyr_left_join_impl`’ not in namespace:
   .Call(`_dplyr_left_join_impl`, x, y, by_x, by_y, suffix_x, suffix_y, 
       na_match)
  symbol ‘`_dplyr_loc`’ not in namespace:
   .Call(`_dplyr_loc`, data)
  symbol ‘`_dplyr_mutate_impl`’ not in namespace:
   .Call(`_dplyr_mutate_impl`, df, dots)
  symbol ‘`_dplyr_n_distinct_multi`’ not in namespace:
   .Call(`_dplyr_n_distinct_multi`, variables, na_rm)
  symbol ‘`_dplyr_plfloc`’ not in namespace:
   .Call(`_dplyr_plfloc`, data)
  symbol ‘`_dplyr_right_join_impl`’ not in namespace:
   .Call(`_dplyr_right_join_impl`, x, y, by_x, by_y, suffix_x, suffix_y, 
       na_match)
  symbol ‘`_dplyr_select_impl`’ not in namespace:
   .Call(`_dplyr_select_impl`, df, vars)
  symbol ‘`_dplyr_semi_join_impl`’ not in namespace:
   .Call(`_dplyr_semi_join_impl`, x, y, by_x, by_y, na_match)
  symbol ‘`_dplyr_setdiff_data_frame`’ not in namespace:
   .Call(`_dplyr_setdiff_data_frame`, x, y)
  symbol ‘`_dplyr_shallow_copy`’ not in namespace:
   .Call(`_dplyr_shallow_copy`, data)
  symbol ‘`_dplyr_slice_impl`’ not in namespace:
   .Call(`_dplyr_slice_impl`, df, dots)
  symbol ‘`_dplyr_strings_addresses`’ not in namespace:
   .Call(`_dplyr_strings_addresses`, s)
  symbol ‘`_dplyr_summarise_impl`’ not in namespace:
   .Call(`_dplyr_summarise_impl`, df, dots)
  symbol ‘`_dplyr_test_comparisons`’ not in namespace:
   .Call(`_dplyr_test_comparisons`)
  symbol ‘`_dplyr_test_grouped_df`’ not in namespace:
   .Call(`_dplyr_test_grouped_df`, data)
  symbol ‘`_dplyr_test_length_wrap`’ not in namespace:
   .Call(`_dplyr_test_length_wrap`)
  symbol ‘`_dplyr_test_matches`’ not in namespace:
   .Call(`_dplyr_test_matches`)
  symbol ‘`_dplyr_ungroup_grouped_df`’ not in namespace:
   .Call(`_dplyr_ungroup_grouped_df`, df)
  symbol ‘`_dplyr_union_data_frame`’ not in namespace:
   .Call(`_dplyr_union_data_frame`, x, y)
See chapter ‘System and foreign language interfaces’ in the ‘Writing R
Extensions’ manual.