https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100474
Enrico Seiler <enrico.seiler at hotmail dot de> changed:
What |Removed |Added
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CC| |enrico.seiler at hotmail dot de
--- Comment #2 from Enrico Seiler <enrico.seiler at hotmail dot de> ---
Here is a version not dependent on range-v3:
https://godbolt.org/z/PvdhxGo5c
```
template <typename T, typename... Args>
concept foo = __is_constructible(T, Args...);
class S
{
public:
S() = delete;
S(S const &) = default;
S(S &&) = default;
S & operator=(S const &) = default;
S & operator=(S &&) = default;
~S() = default;
};
int main()
{
// static_assert(!__is_constructible(S)); // OK
// static_assert(!foo<S>); // OK
// static_assert(__is_constructible(S)); // FAILS
static_assert(foo<S>); // ICE
}
```
The parameter pack is not necessary for the ICE to occur, however, it is what
META_IS_CONSTRUCTIBLE is expanded to in range-v3.
Using `concept foo = static_cast<bool>(__is_constructible(T, Args...));` will
remove the ICE, even though `__is_constructible` should already return a bool.
