Consider the following code:
#include <vector>
extern std::vector<int> const my_vector;
auto const my_vector = std::vector<int>{};
It fails to compile on gcc but it works on clang since 6.0.0:
[x86-64 gcc 8.1 #1] error: conflicting declaration 'const auto my_vector'
Is this a gcc bug or a violation of the spec?
