RE: [avr-gcc-list] Problem with debbuggin with AVRStudio, WinAvr and JtagIce mkII

[Dave Hansen]

From: address@hidden
[...]
> #include <avr/io.h>
>
> int somma(int a, int b)
>
> {
>                 return a+b;
> }
>
> int main ()
> {               int e = 10;
>                 int r = 1;
>                 r = somma(e,r);
>                 r=r+1;
>                                 return r;
> }
>
> it's a stupid program. When debbugging it step by step the main regularly 
> calls somma(e,r).
> After somma(e,r) finished, the control flow does not return in main at 
> r=r+1 but in a part of memory without code  (after the exit() of the main). 
> Can you help me with  this problem?

Just a guess:  Try making 'r' volatile, i.e., change the declaration of r to

  int volatile r = 1;

Because r is not used other than as the return value, the compiler might be 
optimizing out accesses to the variable itself.  The 'volatile' declaration 
forces the compiler to retain these accesses.

HTH,
  -=Dave