Your right I was in a hurry, wife called.....
In Setup add:
Serial.begin(115200);
Then in critial areas add this line;
Serial.print(__LINE__);
This has to be done while still connected to the IDE. And you must open the "Serial Monitor" listed under tools. Then change the baud rate (lower right hand corner) to 115200.
In the Serial Monitor window you will see the line numbers be printed as your code is executed.
If they go too fast, add a delay(2000); at the loop beginning.
BTW I learned something too. I was not aware that __ LINE __ would print the line numbers. I had been doing it manually 