Step into sometimes doesn't work

[PascalA]

After a few steps in a a sketch, it often happens that the step into command doesn't work.

In the same program, it generally works the first times I use it, but I cannot be sure it will work the following time. By not working, I mean the cursor doesn't move. I can use the step command instead which allways works.

If the cursor comes again on a line on which step into didn't work a moment before, the command may work again.

This problem happens really often (less than one minute of testing), but I'm unable to provide a precise sequence to reproduce it.