%Warning-PROCASSINIT: t/t_cover_assert.v:13:18: Procedural assignment to declaration with initial value: 'cyc' : ... note: In instance 't' : ... Location of variable initialization 13 | integer cyc = 0; | ^ t/t_cover_assert.v:19:7: ... Location of variable process write : ... Perhaps should initialize instead using a reset in this process 19 | cyc <= cyc + 1; | ^~~ ... For warning description see https://verilator.org/warn/PROCASSINIT?v=latest ... Use "/* verilator lint_off PROCASSINIT */" and lint_on around source to disable this message. %Error-UNSUPPORTED: t/t_cover_assert.v:39:11: Unsupported: Procedural concurrent assertion with clocking event inside always (IEEE 1800-2023 16.14.6) : ... note: In instance 't' 39 | C1: cover property(a) | ^~~~~ ... For error description see https://verilator.org/warn/UNSUPPORTED?v=latest %Error: Exiting due to