Re: [top-level] C++-friendly allocators for libiberty

[Bernardo Innocenti <bernie@develer.com>]

Daniel Jacobowitz wrote:
> On Sat, Jun 26, 2004 at 04:39:04AM +0200, Bernardo Innocenti wrote:
> 
>>Ian Lance Taylor wrote:
>>
>>>Bernardo Innocenti <bernie@develer.com> writes:
>>>
>>>
>>>
>>>>On second thought, the interface for xrenew() or xresize() wasn't
>>>>even usable without a size argument.
>>>
>>>Oh yeah.
>>>
>>>
>>>
>>>>Maybe this would be better?
>>>>
>>>>  #define xrenewvec(P, T, N)	(T *) xrealloc ((P), sizeof(T) * (N))
>>>
>>>
>>>No, people use realloc with variable size arrays at the end of
>>>structs.  xrenewvec (or xresizevec) is a good idea, but you still need
>>>xrenew (or xresize).
> 
> 
> Bernando, you've now got an interface which allows reallocating to a
> variable size, but not allocating to one...  There's no need for a
> rush, let's give people some time to comment before putting this into
> libiberty.  As DJ says, it's hard to take things out of libiberty.

I've not yet committed anything, but I see your point.

There's good symmetry here:

  struct foo *v = xnewvec (struct foo, 42);
  v = xresizevec (struct foo, v, 666);
  xdeletevec (v);

But not here:

  struct varsize *s = ???
  s = xresize (struct varsize, s, sizeof (struct varsize) + strlen (name));
  xdelete (s);


Maybe we should add this:

  #define xvarnew(T, S)   (T *) xmalloc (S)


Another possibility would be dropping this realloc interface
altogether and sticking with a simpler interface that has
the same limitations of C++.

-- 
  // Bernardo Innocenti - Develer S.r.l., R&D dept.
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