[Bug c++/23383] builtin array operator new is not marked with malloc attribute

["rguenther at suse dot de" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23383

--- Comment #23 from rguenther at suse dot de <rguenther at suse dot de> 2012-01-09 08:37:21 UTC ---
On Thu, 5 Jan 2012, jakub at gcc dot gnu.org wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23383
> 
> Jakub Jelinek <jakub at gcc dot gnu.org> changed:
> 
>            What    |Removed                     |Added
> ----------------------------------------------------------------------------
>                  CC|                            |jakub at gcc dot gnu.org
> 
> --- Comment #21 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-01-05 18:26:17 UTC ---
> But can't a valid code also compare the result from realloc with the old
> pointer, and if they are equal, do something, otherwise do something else?
> I think it is pretty common e.g. if the malloced block contains pointers to
> parts of the malloced area and upon realloc that didn't return the passed
> address wants to adjust all those pointers.

Sure.

> Having a malloc attribute on realloc would still break this.

We cannot use the malloc attribute on realloc, ever.

> I'd say we want realloc attribute and handle it where we currently handle
> BUILT_IN_REALLOC.

Not sure it's worth it besides handling BUILT_IN_REALLOC explicitly.