CONFIG_DEBUG_OPTIMIZATIONS does not allow setting breakpoints anywhere

[Juju]

When debugging the exercise 1 application from `Lesson 2 – Reading buttons and controlling LEDs` of `nRF Connect SDK Fundamentals`, I cannot set a breakpoint wherever I want.

Somehow it is either not picked up or it gets picked the line below.

However, if I debug step by step from the beginning, it can stop on all lines.

In this code:

The 2 lines below get ignored, I cannot break on them:

I am setting CONFIG_DEBUG_OPTIMIZATIONS by selecting:

However, it seems not sufficient as there are probably some optimisations that are made on the code.

I remember when debugging on nRF52, I had to set:

so `-O0 -g3` flags in order to propely debug and I think I need to also enable `CONFIG_NO_OPTIMIZATIONS` but I can't override its value together with `CONFIG_DEBUG_OPTIMIZATIONS`.

Another issue I see is if I put a breakpoint here just before starting to debug:

I get the debugger to stop here:

Any hints?

[Priyanka]

Hi,

Did you enable the following on your prj.conf ?

CONFIG_DEBUG=y

CONFIG_DEBUG_OPTIMIZATIONS=y

CONFIG_NO_OPTIMIZATIONS=y

Regards,

Priyanka

[Juju]

I've modified the prj.conf file as follows:

However it seems that CONFIG_NO_OPTIMIZATIONS is overridden to `n` instead of 'y'.

By the way, I'm using a Mac but it shouldn't make a difference.

[Priyanka]

Hi,

Apologies for the delayed response.

It looks like selecting both 

CONFIG_DEBUG_OPTIMIZATIONS and 

CONFIG_NO_OPTIMIZATIONS

can cause a conflict. So generally you select any one depending on your needs. So please try choosing CONFIG_NO_OPTIMIZATIONS if you want to ensure absolutely no optimization, which makes debugging straightforward and choose CONFIG_DEBUG_OPTIMIZATIONS  if you still want some optimizations but in a way that doesn't interfere too much with debugging.

Please try this and let me know how it goes. 

Regards,

Priyanka

[Juju]

No worries

So here I select any since CONFIG_NO_OPTIMIZATIONS is not possible in the drop down list:

Then in prj.conf I do force CONFIG_NO_OPTIMIZATIONS=y and CONFIG_DEBUG_OPTIMIZATIONS=n:

Then in "Output files" folder I have .config file with:

Somehow I still can't add a breakpoint anywhere I want.

Is .config file the final state or is it overridden by prj.conf?

[Priyanka]

Hi,

Could you tr building with project default ? Does this help?

-Priyanka

[Juju]

Hello

Still not able to put breakpoints where I want and also I get the notification "The selected build configuration does not have debugging options enabled" even though I enable either  CONFIG_NO_OPTIMIZATIONS or CONFIG_DEBUG_OPTIMIZATIONS in the prj.conf file.

[Priyanka]

Hi,

The breakpoint issue you are facing is because of the optimizations that take place. This changes the machine code so that it does not exactly map the C code, so it makes debugging harder. So the only way is to disable all optimizations when debugging. Please take a look at this ticket.

Regards,

Priyanka

[Juju]

I'm sorry but something is wrong with debugging using the dev kit nRF9160 DK.

This should be straightforward.

Below a video, please try to reproduce the issue, I'm not doing anything fancy, just using "fund_less2_exer1_solution" sample code and trying to put a breakpoint in the while loop.

CONFIG_NO_OPTIMIZATIONS=y

CONFIG_DEBUG_OPTIMIZATIONS=y

Please check the following video and let me know:

[Priyanka]

Hi,

I a unable to view the video that you attached. Would it be possible to zip the view and attach the file?

I nevertheless tried to reproduce the issue on my DK here and was not successful. It would be great if you could attach the video once again so that I can see what's happening at your end.

Could you also tell me which SDK version you are working with? And what is your DK revision?

-Priyanka