Why loop variable should not be used in FORK JOIN_NONE

SystemVerilog
3

In reply to dave_59:

Thanks Dave for your suggestion.
I have one more doubt. In the below attached snippet what is the difference if i declare automatic int ch=i inside for_begin block or inside fork_join_none block(as i have commented in the code)
If i use automatic int ch=i inside fork_join_none block ,that statement will also be treated as separate thread and there will be two different threads one is automatic int ch=i and one more is begin_end block inside fork_join_none. And what if begin_end block inside fork_join_none tries to get ch value before it is updated.
NOTE :- I have corrected my typo as you suggested in above reply.


module test;
  class member;   
    task main_task(bit[7:0] a,b,c,d);
      fork 
        sub_task(a,b,"FIRST THREAD");
        sub_task(c,d,"SECOND THREAD");
      join
    endtask
    task automatic sub_task(bit[7:0] p,q,string label);
      bit[7:0] m,n;
      for(int i=0;i<3;i++)
        begin //for begin
         automatic int ch=i;
          fork 
            //automatic int ch=i;
            begin //fork begin
              m=p*ch;
              n=q*ch;
              $display("Tag=%s,m=%0d,n=%0d,i=%0d",label,m,n,i);
            end //fork end
          join_none
        end //for end
    endtask
  endclass
 
  member m1;
  initial begin
    m1=new();
    for(int i=1;i<5;i++) begin
      m1.main_task(i,i+1,i+2,i+3); end
  end
endmodule