unexpected reboots : memory problems ?

hi, i'm not too sure.
i'm able to reproduce the crashes deterministically though.

it's not the jit alone because when disabling it completely i also managed to get the bug.

i figured out that this line (758):

            Bangle.setPollInterval(2000); // disable accelerometer as much as we can (a value of 4000 seem to cause hard reboot crashes (segfaults ?) so keep 2000)

seem to cause problems at 4000. just switching to 2000 it seems there are no problems anymore.

however it's not the end of the story because i have two different methods for which i'd like to use the jit. 'display_tiles' and 'display_thick_tiles'.
when i tried on both it always crashed.
when i tried on 'display_tiles' alone it used to work (before my latest changes on powersaving).
but now after the changes when i try on 'display_tiles' alone the behavior is very strange.
it does not crash but the screen flickers, with the streets not being displayed and i get weird messages in the console about incorrect code which does not exist.

i was wondering if i was hitting some limits on memory size.

if you like i can help you reproduce it.