Re: is this a valid approach to aliasing?

[Andrew Haley <aph@xxxxxxxxxx>]

Robert William Fuller wrote:
> John Love-Jensen wrote:
> > Hi Robert,
> >
> > Can you just get rid of the void** for the items parameter (see below)?
> >
> > --Eljay
> >
> > #include <stdlib.h>
> >
> > int reallocItems(
> >   void* items,
> >   int itemSize,
> >   int* itemAlloc,
> >   int numItems,
> >   int newItems,
> >   int itemHint)
> > {
> >   void* rcAlloc;
> >   int emptyItems;
> >   int allocItems;
> >
> >   // for idempotence
> >   allocItems = *itemAlloc;
> >
> >   // will the new entries fit?
> >   emptyItems = allocItems - numItems;
> >
> >   if (newItems > emptyItems)
> >   {
> >     // allocate the number of entries needed or the hint, whichever is 
> > more
> >     allocItems = numItems + newItems;
> >
> >     if (itemHint > allocItems)
> >     {
> >       allocItems = itemHint;
> >     }
> >
> >     rcAlloc = realloc(items, allocItems * itemSize);
> >
> >     if (rcAlloc)
> >     {
> >       *(void**)items = rcAlloc;

This code is probably wrong.  Make item a void** and get rid of the cast.

Andrew.