WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS

#include <reg51.h>
void delay2s()
{   
  unsigned char i;
  TMOD=0x10;
  for(i=0;i<20;i++)
 {
  TH1=0x3C;
  TL1=0xAF;
  TR1=1;
  while(!TF1);
  TF1=0;
 }
}
void main()
{
   while(1)
   {
       P1=0x01;
       delay2s();
       P1=0x02;
       delay2s();
       P1=0x04;
       delay2s();
       P1=0x08;
       delay2s();
       P1=0x10;
       delay2s();
       P1=0x20;
       delay2s();
       P1=0x40;
       delay2s();
       P1=0x80;
       delay2s();
       P1=0x06;
       delay2s();
       P1=0xC0;
       delay2s();
       P1=0x38;
       delay2s();
       P1=0xFF;
       delay2s();
   }
}