C++ Logo

SG10

Advanced search

Subject: Re: [SG10] bump __cpp_deduction_guides to 201703 for P0620?
From: Jason Merrill (jason_at_[hidden])
Date: 2018-05-30 10:14:14


On Tue, May 29, 2018 at 6:20 PM, Richard Smith <richard_at_[hidden]> wrote:
> Hi,
>
> When implementing some of the recent stdlib class template argument
> deduction changes, we noticed that p0620 substantially changes the rules for
> deduction guides to the point where (eg) our standard library's testsuite
> fails on a compiler that defines __cpp_deduction_guides to the latest
> version described by SD-6.
>
> I suggest we bump the version from 201611 to 201703 for implementations that
> support P0620. (This leaves Clang 6.0.0 as defining the macro to the older
> version but providing the newer functionality, but that seems preferable to
> making the "full" rule set undetectable.)
>
> Thoughts?

Makes sense to me.

Jason


SG10 list run by sg10-owner@lists.isocpp.org