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

[Andrew Hassall]

oh right didn't realise the bytes would be freed straight away, thank
you so much!
by creating variable in this form
"x->win=getbytes(x->winsize*sizeof(t_sample));" do you still refer to
them in the same way as arrays e.g. *(win+10) to get value at index
10?

Thanks!!!
Andy

On Wed, Apr 27, 2011 at 12:59 PM, IOhannes m zmoelnig <zmoelnig at iem.at> wrote:
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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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