Recent change to struct prop breaks examples with NVC++ #1590
Description
PR #1575 causes some of the stdexec examples to fail in the NVHPC automated tests. I believe the problematic line in that PR is:
static_assert(__callable<_Query, __prop_like<_Value>>);The failure is:
"/proj/cuda/stdexec/main/include/stdexec/__detail/__env.hpp", line 252: error: static assertion failed
static_assert(__same_as<decltype(__v<_Result>), const bool>);
^
detected during:
instantiation of "auto stdexec::__queries::__is_scheduler_affine_t::operator()(const _Env &) const noexcept [with _Env=stdexec::__env::__prop_like<stdexec::__mbool<true>>]" at line 398
instantiation of class "stdexec::__env::prop<_Query, _Value> [with _Query=stdexec::__queries::__is_scheduler_affine_t, _Value=stdexec::__mbool<true>]" at line 65 of "/proj/cuda/stdexec/main/include/stdexec/__detail/__then.hpp"
[ ... more instantiation stack ... ]
The examples that are failing to compile are nvexec.maxwell_cpu_mt, nvexec.maxwell_cpu_st, scope, server_theme.on_transfer, server_theme.split_bulk, and server_theme.then_upon.
I haven't looked into this in detail to figure out whether this is an NVC++ compiler bug or a stdexec bug.