This is an example of a piece of C++11 code:
auto text = std::unique_ptr<char>(new char[len]);
Function 'unique_ptr' could not be resolved
I found this article in the Eclipse forum, just followed those steps and it works for me. I am using Eclipse Indigo 20110615-0604 on Windows with a Cygwin setup.
-std=c++0x(or for newer compiler version
-std=c++11at the end . ... instead of GCC C++ Compiler I have also Cygwin compiler
__GXX_EXPERIMENTAL_CXX0X__(ensure to append and prepend two underscores) into "Name" and leave "Value" blank.
There is a description of this in the Eclipse FAQ now as well: Eclipse FAQ/C++11 Features.