Unpacking a std::array

I tried to unpack a std::array via std::tie:

#include <tuple>
#include <array>

int main() {
    std::array<int, 3> arr = {1, 2, 3};
    int a, b, c;
    std::tie(a, b, c) = arr;
    return 0;
}

This works in clang, but fails to compile in g++ 5.4: no match for ‘operator=’. Compile options are -std=c++11.

1. Why does this work in clang but not g++?
2. How can I portably unpack a std::array, like one might unpack a tuple?

Thanks for any help!