[Bug libstdc++/100436] New: std::views::iota(0, true) is well-formed

[Bug libstdc++/100436] New: std::views::iota(0, true) is well-formed

[hewillk at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100436

            Bug ID: 100436
           Summary: std::views::iota(0, true) is well-formed
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hewillk at gmail dot com
  Target Milestone: ---

Hi, The following is accepted since gcc-11:

https://godbolt.org/z/P8v383Wr3

#include <ranges>
auto r = std::views::iota(0, true);

Shouldn't this be ill-formed? Isn’t this kind of initialization explicitly
prohibited in the deduction guides? Correct me if i am wrong, thanks.

[Bug libstdc++/100436] std::views::iota(0, true) is well-formed

[hewillk at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100436

--- Comment #1 from 康桓瑋 <hewillk at gmail dot com> ---
Oh, I see, the reason is that std::ranges::__detail::__is_integer_like<bool> is
set to false since gcc-11.

[Bug libstdc++/100436] std::views::iota(0, true) is well-formed

[hewillk at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100436

康桓瑋 <hewillk at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |INVALID
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #2 from 康桓瑋 <hewillk at gmail dot com> ---
(In reply to 康桓瑋 from comment #1)
> Oh, I see, the reason is that std::ranges::__detail::__is_integer_like<bool>
> is set to false since gcc-11.

This is just the implementation of LWG 3467.

[Bug libstdc++/100436] std::views::iota(0, true) is well-formed

[hewillk at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100436

--- Comment #3 from 康桓瑋 <hewillk at gmail dot com> ---
(In reply to 康桓瑋 from comment #2)
> (In reply to 康桓瑋 from comment #1)
> > Oh, I see, the reason is that std::ranges::__detail::__is_integer_like<bool>
> > is set to false since gcc-11.
> 
> This is just the implementation of LWG 3467.

I think the legality of std::views::iota(-100, false) is just an inadvertent of
LWG 3467.