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Re: [wg14/wg21 liaison] unreachable control flow

From: Aaron Ballman <aaron_at_[hidden]>
Date: Mon, 17 May 2021 09:47:21 -0400
On Mon, May 17, 2021 at 9:44 AM Jonathan Wakely <cxx_at_[hidden]> wrote:
> On Mon, 17 May 2021 at 14:09, Aaron Ballman via Liaison <liaison_at_[hidden]> wrote:
>>
>> On Mon, May 17, 2021 at 8:47 AM Jₑₙₛ Gustedt <jens.gustedt_at_[hidden]> wrote:
>> >
>> > Aaron,
>> >
>> > on Mon, 17 May 2021 07:01:33 -0400 you (Aaron Ballman
>> > <aaron_at_[hidden]>) wrote:
>> >
>> > > On Sun, May 16, 2021 at 6:13 AM Jₑₙₛ Gustedt via Liaison
>> > > <liaison_at_[hidden]> wrote:
>> > > >
>> > > > Hello,
>> > > > it seems that C++ has integrated
>> > > >
>> > > > https://wg21.link/p0627
>> > > >
>> > > > into C++20. This provides a pseudo-function `unreachable` where a
>> > > > call indicates that the whole path in the control flow that reaches
>> > > > it can never be taken.
>> > > >
>> > > > Is there interest / attempt / opposition of porting this feature to
>> > > > C?
>> > >
>> > > Personally, I'm in favor of the idea -- the proposed functionality
>> > > applies in C with the same general rationale (alongside similar C
>> > > functionality as _Noreturn and assert), and it would be handy to add
>> > > this functionality to C's toolbox.
>> >
>> > Great, so far the only reactions that I have been seeing here are
>> > favorable. In contrast to that, the state of the proposal is somehow
>> > unknown? Is there a way to know better where this is stuck, currently?
>>
>> WG21 tracks all of their papers using GitHub issues so that you can
>> see the state of a given proposal. According to the issue for this
>> paper (https://github.com/cplusplus/papers/issues/275), it looks like
>
>
> Which you can jump to using the https://wg21.link/p0627/github shortcut.

TIL something life-changing.

>> this was last seen in Prague 2020 and needs additional revision. To
>> see what feedback was given in Prague, you can check out the WG21 wiki
>> (it uses the same password as the SG22 monthly meeting Zoom password):
>
>
> N.B. please don't edit anything without checking with somebody first!
>
> (Obvious typos are probably OK, but even then the wiki software doesn't cope well with concurrent edits, so be very cautious about any changes to a page you don't "own").

+1, and this also goes for uploading new contents to the wiki (as some
ways of uploading may try to update pages that others are concurrently
editing).

~Aaron

>
>
>
>>
>> https://wiki.edg.com/bin/view/Wg21prague/ (likely somewhere under the
>> Library Working Group heading as they were the last group to see this
>> according to the GitHub issue).
>
>
> Searching for the paper number using the search box in the top-right corner usually finds the relevant discussion.
>

Received on 2021-05-17 08:47:37