Upgrading from GCC 4.8.2 to GCC 4.9.0 without a complete rebuild

Question

I installed the GCC 4.8.2 a couple of weeks ago. The installation process went well and I have GCC 4.8.2 at my Ubuntu system (12.04 64 bits). Now GNU just released the newer version 4.9.0.

My question is: Is there any way to upgrade my GCC to 4.9.0 without doing all process: configuration, building, checking and installation from scratch? Also, please tell me what is the benefit/purpose of gcc-4.8.2-4.9.0.diff.gz file? Is it like script/patch file to upgrade my compiler?

FYI, I don't have any plan to have two different versions of GCC at my system.

Answer 1

My question is: Is there any way to upgrade my GCC to 4.9.0 without doing all process: configuration, building, checking and installation from scratch?

Yes, if you have it already built. No, if you have only sources.

Also, please tell me what is the benefit/purpose of gcc-4.8.2-4.9.0.diff.gz file?

Read manual for patch utility how to apply it. You can convert 4.8.2 sources to 4.9.0 ones with this diff.

Is it like script/patch file to upgrade my compiler?

Yes, but for its sources. So building is still required.

Do you really need new features of 4.9 for your projects?