Does gcc 4.3.4 support unique_ptr? - c++11

Question

I've been trying to implement PIMPL using the g++ compiler on my local CygWin install and I'm beginning to think it may be the fact that I'm running g++ 4.3.4, inasmuch as its C++11 support is less than perfect.
With the very baseline code (from MSDN here):
my_class.h:
#include <memory>
class my_class {
public:
my_class();
private:
class impl; unique_ptr<impl> pimpl(new impl);
};
my_class.cpp:
#include "my_class.h"
class my_class::impl { int my_int; };
my_class::my_class(): pimpl( new impl ) {};
I try to compile with g++ -std=c++0x -o my_class.o my_class.cpp and end up with:
In file included from my_class.cpp:1:
my_class.h:8: error: ISO C++ forbids declaration of 'unique_ptr' with no type
my_class.h:8: error: invalid use of '::'
my_class.h:8: error: expected ';' before '<' token
my_class.cpp: In constructor 'my_class::my_class()':
my_class.cpp:5: error: class 'my_class' does not have any field named 'pimpl'
I also get that if I substitute -std=gnu++0x.
In fact, when I try to compile even the simplest file, lifted from another SO answer:
#include <iostream>
#include <memory>
int main() {
std::unique_ptr<int> up( new int( 30 ) );
}
it complains that unique_ptr is not in the std namespace.
The gcc c++11 support page has no entry for unique_ptr but, from looking at the net, it's been around for quite a while, at least since 4.4.
So my question is, firstly, at what version of gcc was support for unique_ptr added?
And, secondly, am I just making some bonehead mistake in my code, using it the wrong way?

Answer 1

In your first example, the std:: qualifier is missing on unique_ptr. The second example is correct C++11.
According to the GCC 4.4 release notes, unique_ptr was not in GCC's standard C++ library before 4.4:
Improved experimental support for the upcoming ISO C++ standard, C++0x, including:
...
unique_ptr, <algorithm> additions, exception propagation, and support for the new character types in <string> and <limits>.