Re: Is there any plans or work going on gcc related to c++ coroutines?

[Avi Kivity <avi at scylladb dot com>]

On 08/19/2017 12:19 PM, Andrew Haley wrote:
> > Really take boost.coroutine2, some Macro ridden coroutine libraries,
> > or any c coroutine task library and compare what N4680 draft proposes.
> > Which of them is feel more natural and easier integrate to base C++?
> >
> > No one suggests it is "critical". But do not think that interest is
> > special or strange, it just isn't.
> Oh, please.  SIMULA had coroutines working perfectly well, and they
> were very useful, and that was *exactly* fifty years ago!  I am just
> amused, that is all.
>
> But there is a serious question behind all of this: why now?
> Coroutines are not particularly difficult to implement, and could have
> been done at any time.  I'm not opposed to doing it now!

There is some confusion here. Stackful coroutines are available for C 
and C++ since forever, and don't require compiler support. I've written 
such libraries at least twice, and perhaps more.

Stackless coroutines require compiler support for C and C++, and have 
been made available for other popular languages recently. Like I 
mentioned elsewhere, they are very useful for asynchronous programming, 
and also for implementing complex iterators and generators in a simple way.

As to why now? They are being standardized now. Why are they being 
standardized now? Pressure from other popular languages, and 
standardization backlog, perhaps.