My program runs fine on uvision simulation (nothing to do with Silab peripherials). Same program shows (long multiplied by long) calling C:0000 My tool integration shows both, uvision and Silab are using same programs. Silabl people could not help.
Well, that's clearly an Si Labs problem - so you'll have to ask Si Labs! What compiler is the SiLabs IDE using? Are you sure you are looking at the final, linked code from Si Labs? Do you get an errors/warnings from the SiLabs tools?