Indeed, it's a known issue and Andrei already investigated it. There is a discussion on the Pharo-dev mailing list.

Cheers,

Doru

On Sun, May 3, 2015 at 11:11 PM, Alexandre Bergel <alexandre.bergel@me.com> wrote:

Hi!

When tracing the execution in GT-debugger the text selection does not always reflect the real position of the program counter. Consider the following screenshot:

I have simply pressed the step-into button, nothing more. The selection is not meaningful.
Am I the only one to have noticed this?
It would be great to have it fixed…

Cheers,
Alexandre

--
_,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:
Alexandre Bergel http://www.bergel.eu
^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;.

www.tudorgirba.com

"Every thing has its own flow"