We'll presumably need both a language component and a library component, but user code will only want to test one macro.

Perhaps the compiler should define a macro for language support and the library should only define its macro if the compiler macro is defined (as min(compiler macro value, library value)?).

On Fri, 3 Aug 2018, 11:45 Ville Voutilainen, <ville.voutilainen@gmail.com> wrote:
On 3 August 2018 at 21:23, Chris Kennelly <ckennelly@google.com> wrote:
> P0722, adopted at Rapperswil, added destroying operator delete.  Would it be
> possible to provide a feature test macro for its availability?

..presumably so that you can declare such an operator only if the
macro is defined, so as to
avoid otherwise ill-formed code because std::destroying_delete_t
wouldn't be available?

Makes sense to me.
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