verilator/test_regress/t/t_clk_gate_ext.v

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain.
// SPDX-FileCopyrightText: 2020 Wilson Snyder
// SPDX-License-Identifier: CC0-1.0

module t (  /*AUTOARG*/
    // Inputs
    clk
);
  input clk;

  reg clk_en = 1'b0;
  wire clk_gated = clk & clk_en;
  wire [1:0] clks = {1'b0, clk_gated};

  always @(posedge clks[0]) begin
    $display("ERROR: clks[0] should not be active!");
    $stop;
  end

  int cyc = 0;
  always @(posedge clk) begin
    cyc <= cyc + 1;
    if (cyc == 99) begin
      $write("*-* All Finished *-*\n");
      $finish;
    end
  end

endmodule