Why is this an issue?

A case statement is statically known to not select any branch, because none of the items match the known constant expression and there is no default label.

How to fix it

Code examples

Noncompliant code example

module fly;
  always_comb begin
    case (1)
      2: begin end
      3: begin end
      4: begin end
    endcase
  end
endmodule