Problems when alsmot filling flash memory

[OT]

In several projects lately I have found that when less than about 10% free of ROM is reported, the program executes erratically - giving nonsense problems. The lower I get the more problems This can for instance to begin with manifest itself that an instruction is not carried out as expected, while even lower free program ROM can cause the code not working at all. Any consensus from ME and other users why this happens? Is reported free ROM inaccurate?
While I am mostly using ver. 6.2.1, I have briefly tested identical code on ver 7.01 in a VM and see exactly the same behavior.

[dusan.poluga]

Hi,

Can you provide an example that can reproduce this behavior ?

Best Regards,

[OT]

Unfortunately , by the nature of the problem (filling up program memory), these are big complicated projects that require hardware and/or MCU models usually not supported by your development boards. Thus you would have no easy way to run and test them.