What does the javac debugging information option -g:vars do?

Question

What exactly the -g:vars (local variable debugging information) option of javac provides as output.

Doing some tests, there is no addition information (

Answer 1

From the javadocs:

-g Generate all debugging information, including local variables. By default, only line number and source file information is generated.

This does not produce visible output at compile time but is used in debugging during run time.