[libcxx-commits] [libcxx] [libc++] Remove SFINAE on __tuple_impl constructors (PR #151654)

[Alexander Kornienko via libcxx-commits]

alexfh wrote:

> Aha, I've reduced the example to:
> 
> ```c++
> template<class>
> struct Trait;
> 
> template<class T>
> constexpr bool TraitV = Trait<T>::value;
> 
> template<class T>
> struct S {
>     S() noexcept(TraitV<T>) = default;
> };
> 
> template<class T>
> struct S2 : S<T> {};
> 
> S2<char> s;
> ```
> 
> [Godbolt link](https://gcc.godbolt.org/z/1aMfzr435)
> 
> This should be [ crash-on-invalid](https://github.com/llvm/llvm-project/labels/crash-on-invalid) .

Thanks for reducing this! The crash doesn't reproduce after https://github.com/llvm/llvm-project/pull/154517, so it's indeed a crash-on-invalid. Filed https://github.com/llvm/llvm-project/issues/155320

https://github.com/llvm/llvm-project/pull/151654