Umable to compile the following threads example with G++ 4.5.3, any ideas how to fix?

I get the following error when trying to compile with GNU G++ 4.5.3, how
can I change it to get it to build?

$ g++ -std=gnu++0x threads1.cpp -o threads1
threads1.cpp: In function =E2=80=98int main()=E2=80=99:
threads1.cpp:18:57: error: expected =E2=80=98)=E2=80=99 before =E2=80=98;=
=E2=80=99 token
threads1.cpp:21:15: error: expected initializer before =E2=80=98:=E2=80=99 =
token
threads1.cpp:27:2: error: expected primary-expression before =E2=80=98retur=
n=E2=80=99
threads1.cpp:27:2: error: expected =E2=80=98)=E2=80=99 before =E2=80=98retu=
rn=E2=80=99

#include <iostream>
#include <vector>
#include <thread>
#include <functional>

void func(int& counter)
{
    for (int i = 0; i < 10000; ++i)
        ++counter;
}

int main()
{
    int counter = 0;
    std::vector<std::thread> threads;
    for (int i = 0; i < 10; ++i)
    {
        threads.push_back(std::thread{func, std::ref(counter)};
    }

    for (auto& t : threads)
    {
        t.join();
    }

    std::cout << "Result = " << counter << '\n';
    return 0;
}

--
Tactical Nuclear Kittens