> > What I see no is that when the while loop at the beginning is compiled > > into the code, everything is running OK, but when I comment it out, so > > it is not in de code, the stack check fails, indicating that __bss_end > > and __bss_end + 1 no longer have the specific test values. > > > > If you are using interrupts than you might (by accident) be waiting for > the moment that no interrupts are being executed. And thus no extra > stack usage during your function execution. > > The code size increment is due to a smart optimization. You force > app_TXIncomming to be zero before continuing, gcc notes it and does not > do a multiply that saves some pointer calculation and therefore space. > So your loop is doing something after all ;) > > This also indicates app_TXIncomming as not being volatile? Or a gcc > optimizer bug. > > HTH, > > Wouter
Ok, I did not expect AVR-GCC to be so smart that it would omit the pointer calculations, because the while loop would cause app_TXIncomming to be 0, that is nice optimizing. However, what I don't understand is that the while loop does not cause some stack overflow, because I have decreased the array to be only a single element, so app_TXIncomming is always 0, so the while loop should therefore never loop. It is true that there are a number of interrupts running in the background, but they run in both cases, so that should not make a difference. Oh and yes, app_TXIncomming is not volatile, making it volatile does not change the behavior, the code always sees a stack overflow when the while loop is commented out and no stack overflow when the while loop is included. I will continue to trace my problem, the issue with the difference in generated assembly is now clear to me, I can cross that of my list of things to look at. Thanks for the explanation. Greetings, Han __________ Information from ESET NOD32 Antivirus, version of virus signature database 4827 (20100202) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-gcc-list
