Re: [RFC] Marking C++ new operator as malloc?

[Martin Jambor <jamborm at matfyz dot cz>]

Hi,

On Sun, Sep 09, 2007 at 12:56:25PM -0700, Mark Mitchell wrote:
> For a particular implementation of "operator new" (such as the one in
> libstdc++), you can of course make it safe in the same way as "malloc";
> hide the implementation somewhere the rest of the program can't see it
> (modulo LTO).  But, to declare it with the "malloc" attribute in the
> headers seems dangerous, since we have no way of knowing if the user
> replaced it, off in some file somewhere we don't know about, but in such
> a way that pointers in our source code are being laundered back to us.

All I attempted  to do was to mark  just one particular implementation
of the  new operator  which also happened  to be the  default built-in
one. From my experiments, it appears  that marking it as malloc in the
libstc++ headers  does not affect other  implementations.  However, as
Gabriel Dos Reis  correctly pointed out, the attribute  is not applied
to the new operator if the changed declaration is not somehow included
in  the  compiled source.   Fixing  this  inconsistency requires  some
changes in  the FE.  Nevertheless, so  far I do not  see problems with
declaring standard new implementation as malloc in the header file.

I hope you all agree that  marking the default (and only the default),
implementation as  malloc is worthwhile  and will look into  it(, even
though it is going to take some time).

Martin