On Wednesday 12 May 2004 02:33, Mauricio Scaff wrote:
> Hi,
> I have a lot of questions :
>
> 1) How do I know what have changed between 2 mspgcc releases ? Is there
> some ChangeLog file ?
>
normally, we use 3.2 release. So, if new feature being added to the compiler,
I post announcement here.
> 2) Is there some way to know the maximum stack size used by a program or I
> must look at the assembly code and start counting ?
>
you have to check an assembly code if you want to know it before mcu burning,
or use built-in variable to check it at run time (explained in docs)
> 3) Why :
> while (cnt--)
> {
> anything.....
> }
>
it compiles into:
if not cnt skip loop
else
decrement cnt
execute loop
if cnt goto decrement loop, again;
> compiles using two comparisions of cnt ?
> while (cnt)
> {
> cnt--;
> anything...
> }
> works fine.
both work fine :)
>
> 4) Why the flag -O1 generates a smaller code than -O2 and -Os ?
>
This is a size vs. run time performance thing.
However, sometimes -O2 produces smaller code than -O1.
It depends mostly on stack requirements.
> Thanks, Mauricio
have fun,
~d
