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Re: [PATCH 09/11] Add c++14 sized deallocation operator


On Mar 21 12:35, Peter Foley wrote:
> On Sun, Mar 20, 2016 at 7:28 AM, Corinna Vinschen
> <corinna-cygwin@cygwin.com> wrote:
> > This looks incomplete to me.  Don't we have to export the symbol?
> 
> I don't believe so.
> As I understand it, if you're overriding the standard c++ delete
> implementation, starting with c++14, you also need to provide an
> implementation of the sized deallocation operator, which is designed
> to increase performance of deallocation if the size of the object to
> be deallocated is known.
> See http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3663.html
> However, the sized deallocation operator can simply be defined as an
> call to the original delete operator, which simply preserves the
> current behavior.

But we export these functions as fallback functions to the applications.
See libstdcxx_wrapper.cc and the end of cxx.cc.  While the comment in
cxx.cc claims that this should "not be used in practice", there might be
c++14 code ending up with undefined references to the new delete
operator, isn't it?

https://cygwin.com/ml/cygwin-patches/2009-q3/msg00010.html outlines
why these exports were necessary in the first place.


Thanks,
Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Maintainer                 cygwin AT cygwin DOT com
Red Hat

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