[PD-dev] Pointers changing/corrupting (used to be "signal nan values")

[IOhannes m zmoelnig]

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some more comments, to fill in the gaps:

On 2011-04-27 13:51, IOhannes m zmoelnig wrote:
> a quick glance at lpcanalysis_tilde_new() reveils, that you are
> allocating data on the stack (which will be freed as soon as you leave
> lpcanalysis_tilde_new()!), store their addresses and re-use them later
> (when the memory is already freed).

which is not a good idea.
instead, you have to allocate on the heap, and manually free once you
don't need the data anymore.

> 
> you cannot do:
> <ko>
> void*lpca_new() {
>  //...
>  t_sample winlis[2088];
>  x->win=winlis;
>  //...
> }
> </ko>
> 
> instead you have to do:
> <ok>
> void lpca_free(x) {
>  freebytes(x->win);

which really should read:
freebytes(x->win, 2088*sizeof(t_sample));

>  //...
> }
> void*lpca_new() {
>  //...
>  x->win=getbytes(2088*sizeof(t_sample));
>  //...
> }
> </ok>

and of course it would be nice, if 2088 was not hardcoded, but insteadbe
settable; e.g.
<nice>
void lpca_free(x) {
 freebytes(x->win, x->winsize*sizeof(t_sample));
 //...
}
void*lpca_new() {
 //...
 x->winsize=2088;
 x->win=getbytes(x->winsize*sizeof(t_sample));
 //...
}
</nice>


fgmasdr
IOhannes


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