%Error: t/t_clocking_bad4.v:23:15: Skew must be constant (IEEE 1800-2017 14.4)
                                 : ... In instance t
   23 |        input #cyc in;
      |               ^~~
%Error: t/t_clocking_bad4.v:24:16: Skew cannot be negative
                                 : ... In instance t
   24 |        input #(-1) out;
      |                ^
%Error: t/t_clocking_bad4.v:31:11: Usage of cycle delays requires default clocking (IEEE 1800-2017 14.11)
                                 : ... In instance t
   31 |    always ##1;
      |           ^~
%Error: t/t_clocking_bad4.v:32:15: Only non-blocking assignments can write to clockvars (IEEE 1800-2017 14.16)
                                 : ... In instance t
   32 |    always cb1.out = clk;
      |               ^~~
%Error: t/t_clocking_bad4.v:33:15: Only non-blocking assignments can write to clockvars (IEEE 1800-2017 14.16)
                                 : ... In instance t
   33 |    assign cb1.out = clk;
      |               ^~~
%Error: t/t_clocking_bad4.v:34:21: Only non-blocking assignments can write to clockvars (IEEE 1800-2017 14.16)
                                 : ... In instance t
   34 |    always write(cb1.out);
      |                     ^~~
%Error: t/t_clocking_bad4.v:35:22: Event controls cannot be used in synchronous drives (IEEE 1800-2017 14.16)
                                 : ... In instance t
   35 |    always cb1.out <= @(posedge clk) 1;
      |                      ^
%Error: t/t_clocking_bad4.v:36:22: Only cycle delays can be used in synchronous drives (IEEE 1800-2017 14.16)
                                 : ... In instance t
   36 |    always cb1.out <= #1 1;
      |                      ^
%Error: t/t_clocking_bad4.v:37:18: Cycle delays not allowed as intra-assignment delays (IEEE 1800-2017 14.11)
                                 : ... In instance t
   37 |    always out <= ##1 1;
      |                  ^~
%Error: t/t_clocking_bad4.v:40:12: Cannot write to input clockvar (IEEE 1800-2017 14.3)
                                 : ... In instance t
   40 |        cb1.in = 1;
      |            ^~
%Error: t/t_clocking_bad4.v:41:21: Cannot read from output clockvar (IEEE 1800-2017 14.3)
                                 : ... In instance t
   41 |        $display(cb1.out);
      |                     ^~~
%Error: Exiting due to