verilator/test_regress/t/t_event_dynamic_wait.v

// DESCRIPTION: Verilator: dynamic wait on stale class event
//
// This file ONLY is placed under the Creative Commons Public Domain.
// SPDX-FileCopyrightText: 2026 Wilson Snyder
// SPDX-License-Identifier: CC0-1.0

class EventHolder;
  event ev;
  time t_wait = '0;

  task wait_once;
    @ev;
    t_wait = $time;
  endtask
endclass

module t;
  EventHolder h;

  initial begin
    h = new;

    // Leave the event in the fired state before a class-method event control
    // starts. Dynamic waits must pre-clear this stale state before evaluating.
    ->h.ev;
    #10;

    fork
      begin
        #10->h.ev;
      end
      begin
        h.wait_once;
      end
    join

    if (h.t_wait != 20) begin
      $display("%%Error: wait time=%0d expected=20", h.t_wait);
      $stop;
    end

    $write("*-* All Finished *-*\n");
    $finish;
  end
endmodule