Author Name: Jonathan Kimmitt (@jrrk2)
Original Redmine Issue: 1380 from https://www.veripool.org

Original Assignee: Wilson Snyder (@wsnyder)

module bigint(input clk, output reg [128:0] cnt);

    always @(posedge clk)
      cnt = cnt + 129'hdeadbeefc001f00ddeadbeefc001f00ddeadbeefc001f00ddeadbeefc001f00d;

endmodule // bigint

In the above code no warnings are issued when the 256 bit number is silently truncated to 129 bits. However if the 129 is changed to 128, the correct message 'too many digits', is correctly issued. Feel free to use this for the regression suite if wanted.