%Warning-CASEOVERLAP: t/t_priority_case.v:34:7: Case item ignored: every matching value is covered by an earlier condition 34 | 2'b ?1: out1 = 3'd1; | ^~~~~~ t/t_priority_case.v:33:7: ... Location of previous condition 33 | 2'b ?1: out1 = 3'd0; | ^~~~~~ ... For warning description see https://verilator.org/warn/CASEOVERLAP?v=latest ... Use "/* verilator lint_off CASEOVERLAP */" and lint_on around source to disable this message. %Warning-CASEOVERLAP: t/t_priority_case.v:44:7: Case item ignored: every matching value is covered by an earlier condition 44 | 2'b ?1: out1 = 3'd1; | ^~~~~~ t/t_priority_case.v:43:7: ... Location of previous condition 43 | 2'b ?1: out1 = 3'd0; | ^~~~~~ %Error: Exiting due to