On Sat, 21 Sept 2024, 18:37 Julian Waters via Std-Proposals, <
std-proposals_at_[hidden]> wrote:

> Hi all,
>
> I just noticed a strange thing in the language. If one deletes operator
> delete for a specific class, it becomes entirely impossible to create an
> object instance of that class with new expressions if exception handling is
> enabled and one is using a conforming compiler, since new expressions call
> operator delete to deallocate allocated memory if an exception is
> encountered. Nothing can be used to bypass this oddity in the language,
> from marking constructors and every method called in them as noexcept, to
> using LTO to allow the compiler to discern whether the constructor ever
> throws or not, for the simple reason that "the operator delete function is
> named by the new expression, regardless of whether the initialization can
> throw". This effectively means you cannot delete operator delete ever if
> you want to create an object instance of that class using new, unless you
> use language extensions, turn off exception handling entirely for C++, or
> otherwise use a non conforming compiler, which would pretty much mean
> you're not using C++, but one of many dialects of it. There are many usages
> of deleted operator delete, with one example off the top of my head being
> custom memory allocators in the HotSpot Java Virtual Machine (
> https://github.com/openjdk/jdk/blob/2461263aac35b25e2a48b6fc84da49e4b553dbc3/src/hotspot/share/memory/allocation.hpp#L391),
> so this seems like a strange limitation to me,
>

But this example explicitly deletes operator new as well, so it doesn't
matter that deleting operator delete also does that.




is this intended or an oversight?
>
> best regards,
> Julian
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