Re: OT: Possible memory leak in an exercise of a C handbook

[Michael Kjörling <c9bc136c6063@ewoof.net>]

On 16 Dec 2024 17:21 +0100, from martellif67@gmail.com (Franco Martelli):
>> Put in something to count the number of calls to malloc() and free()
>> respectively. Don't forget calls outside of loops.
> 
> There isn't calls to malloc() or free() outside loops. What do you mean?

>From a quick re-glance through your code...

        if ( head == NULL )
        {
==>             head = last = (DIGIT *) malloc( sizeof ( DIGIT ) );
                head->dgt = last->dgt = i;
                head->next = head->prev = last->next = last->prev = NULL;
                return;
        }
        /* Otherwise, find the last element in the list */
        for (p = head; p->next != NULL; p = p->next)
                ; /* null statement */

==>     p->next = (DIGIT *) malloc( sizeof ( DIGIT ) );

and

        for ( const DIGIT *p = head; p->next != NULL; p = p->next )
                if ( p->prev != NULL )
                        free( p->prev );
==>     free( last );

certainly look to me like they're outside of loops.

-- 
Michael Kjörling
🔗 https://michael.kjorling.se