App startup code doesn't start on Symbian Belle, used to run fine

On the device, my code crashes after it has executed the constructor of the CApaApplication with the error: "An invalid instruction exception has occurred."

There is no source, but the crash is at "No source available for "[Unknown] at 0x8e8c" ". This is in debug build, and this very code has been running fine up and until Symbian Anne. The problem is on Symbian Belle. The S60 5th ed app doesn't start either, while it worked absolutely fine on devices up and until Symbian Anna.

The exception looks like there is an invalid instruction being generated. However, this is compiled using the official ARM compiler, which I expect to work flawlessly, given the about of money it costed me.

You should check the actual panic code for the crash. Also if you have used any API which is not shipped with public SDKs, I would suggest checking what they were supposed to work on.