SV: [Icc-avr] Freeing static variables

[Richard]

If you really must. Don't blame me if your program gets non-readable:

In a .s file,
         .area bss
_name1::
_name2::
...
         .blkb 2


now in C,
extern unsigned name1, name2;

Both will have the same address.

Yes, malloc does work

At 02:38 AM 10/22/2007, Bengt Ragnemalm wrote:
>The purpose is just to use less RAM. My problem is that I must run this
>during the normal execution of the full program and not just prior starting.
>
>I can see several solutions to this but none that I can call well written
>code.
>
>Would malloc even work in ICCAVR? I have no idea how it works but I am aware
>of the function.
>
>/Bengt
>
> > -----Ursprungligt meddelande-----
> > Från: icc-avr-bounces at imagecraft.com [mailto:icc-avr-
> > bounces at imagecraft.com] För David Brown
> > Skickat: den 22 oktober 2007 11:27
> > Till: Discussion list for ICCAVR and ICCtiny Users. You do NOT need
> > tosubscribe to icc-announce if you are a member of this.
> > Ämne: Re: [Icc-avr] Freeing static variables
> >
> >
> > By their very definition, "static" variables are allocated a fixed
> > address in memory by the linker, and cannot be "freed".  You have to
> > figure out why you might want to re-use the space they take - if you are
> > using heap-allocated dynamic memory (a terrible idea on most embedded
> > systems!), for example, then you could use malloc and free for the
> > calibration data.  If you need it for other specific purposes after
> > calibration, you could do something like define a union containing a
> > calibration data structure and a run-time data structure, as long as you
> > are careful to track which one is valid.
> >
> > mvh.,
> >
> > David
> >
> >
> > Bengt Ragnemalm wrote:
> > > Is there any intelligent way to release the memory used by a static
> > > variable?
> > >
> > >
> > >
> > > I have a calibration routine that is run the first loops of the program.
> > > If the calibration was done in a separate function , I could just use
> > > temporary variables but as this is run in the entire normal program loop
> > > I can not see any other way than to use statics for my temporary
> > > variables in the calibration routine.
> > >
> > >
> > >
> > > But after the calibrating is done, it would have been nice to free the
> > > space used by the static variables.
> > >
> > >
> > >
> > > Maybe there is some better way to do this so any suggestions are
> > welcome.
> > >
> > >
> > >
> > > Regards,
> > >
> > > Bengt

// richard (This email is for mailing lists. To 
reach me directly, please use richard at imagecraft.com)