Am Samstag, den 12.11.2022, 01:09 +0000 schrieb Joseph Myers: > On Fri, 11 Nov 2022, Martin Uecker via Gcc wrote: > > > > Even a compiler extension requires the level of detail of specification > > > that you get with a WG14 paper (and the level of work on finding bugs in > > > that specification), to avoid the problem we've had before with too many > > > features added in GCC 2.x days where a poorly defined feature is "whatever > > > the compiler accepts". > > > > I think the effort needed to specify the feature correctly > > can be minimized by making the first version of the feature > > as simple as possible. > > The version of constexpr in the current C2x working draft is more or less > as simple as possible. It also went through lots of revisions to get > there. I'm currently testing an implementation of C2x constexpr for GCC > 13, and there are still several issues with the specification I found in > the implementation process, beyond those raised in WG14 discussions, for > which I'll need to raise NB comments to clarify things. constexpr had no implementation experience in C at all and always suspected that C++ experience should somehow count is not really justified. > I think that illustrates that you need the several iterations on the > specification process, *and* making it as simple as possible, *and* > getting implementation experience, *and* the implementation experience > being with a close eye to what it implies for all the details in the > specification rather than just getting something vaguely functional but > not clearly specified. I agree. We should work on specification and on prototyping new features in parallel. Martin
