C++11 (std=c++0x) support on Vortex86DX i486 hardware and gcc

I´m building a project that I need to run in a Vortex86DX i486 embedded system. It comes with a so called D&P XLinux (http://ift.tt/1KQlwzw).

There I need support for C++11 (std=c++0x), where the compiler that comes with the board does not support - gcc version 3.2.3.

I was checking the GCC page to check how shall I upgrade my current compiler and I have my doubts about how to upgrade the compiler and choose the correct version:

a) Which is the first GCC version that supported C++11 ? b) Does that version has support for i486 ? Can I built it for my Vortex hardware ? c) Is there a better approach to support C++11 on this hardaware ?

In fact, my other alternative is to change the code not to use C++11. That will be a huge effort and some libraries (like cryptopp) may make this very problematic.

Thanks for hints and help.