Workaround for https://github.com/Project-OSRM/osrm-backend/pull/4385, C++ (vc++)

Workaround for https://github.com/Project-OSRM/osrm-backend/pull/4385

// Try at https://godbolt.org/g/Jr44iX
// BUG:
// ...\msvc\14.10.25017\include\array(181): error C2440: 'return': cannot convert from 'const char *' to 'const char (&)[256]'
// FIX:
// - either remove const qualifier from Names::get
// - or compile with -DENABLE_MSVC_WORKAROUND
// - or compile with -D_ITERATOR_DEBUG_LEVEL=0
#include <algorithm>
#include <array>
#include <cassert>
#include <string>

#include <iostream>
#include <typeinfo>

constexpr auto N = 256U;
constexpr auto M = 8U;
using NameArray = std::array<char[N], M>;

struct Names
{
    NameArray names;

void set(std::size_t const index, std::string const& name)
    {
        assert(index < M);
        char* dest = names[index];
        auto const count = std::min<std::size_t>(name.length() + 1, N - 1);
        std::copy_n(name.c_str(), count, dest);
    }

std::string get(std::size_t index) const
    {
        assert(index < M);
#ifdef ENABLE_MSVC_WORKAROUND

auto names_ncv = const_cast<NameArray&>(names);
        return std::string(names_ncv[index]);
#else
        std::cout << "names type = " << typeid(names).name() << "\n";
        std::cout << "names[index] type = " << typeid(names[index]).name() << "\n";
        std::cout << "std::begin(names) type = " << typeid(std::begin(names)).name() << "\n";
        std::cout << "std::begin(names) + index type = " << typeid(std::begin(names) + index).name() << "\n";
        const auto &x = std::begin(names) + index;
        std::cout << "x type = " << typeid(x).name() << "\n";
        std::cout << "*x type = " << typeid(*x).name() << "\n";
        return std::string(*x);
#endif
    }
};

int main()
{
    Names names;
    names.set(0, "John");
    std::cout << "Hello " << names.get(0) << "\n";
    return 0;
}


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