Extended Description

The following snippet fails on clang with :
"static_assert failed "std::visit requires the visitor to be exhaustive."
Both gcc and vc++ accept non-const lvalue references.

#include
#include

struct A { int x = 33; };

struct Visitor
{
void operator()(A &node) { std::cout << node.x; }
};
int main()
{
std::variant var = A{};
std::visit(Visitor{}, var);
}