%Error-UNSUPPORTED: t/t_iff.v:66:15: Unsupported: event expression 'iff' 66 | always @(d iff enable) begin | ^~~ ... For error description see https://verilator.org/warn/UNSUPPORTED?v=latest %Error-UNSUPPORTED: t/t_iff.v:71:23: Unsupported: event expression 'iff' 71 | always @(posedge d iff enable) begin | ^~~ %Error-UNSUPPORTED: t/t_iff.v:76:23: Unsupported: event expression 'iff' 76 | always @(negedge d iff enable) begin | ^~~ %Error-UNSUPPORTED: t/t_iff.v:81:20: Unsupported: event expression 'iff' 81 | always @(edge d iff enable) begin | ^~~ %Error-UNSUPPORTED: t/t_iff.v:86:35: Unsupported: event expression 'iff' 86 | assert property (@(posedge clk iff enable) | ^~~ %Error: Exiting due to