Which compiler did macport use?

I'm working on a c++ project which just implemented some of the shared pointer features from boost and/or TR1. Since the upgrade, my code no longer compiles with 开发者_StackOverflowgcc 4.2.1 (provided by Xcode), I'm installing gcc 4.5.x which is suppose to provide the aforementioned features. I need to recompile mpich2 (and then my code) with the new compiler and I want to be sure macport is using the right one.

sudo port install gcc45
gcc_select mp-gcc45

should have gotten the job done, but I'd like port to tell me which compiler it is using. Can anyone help me with this?

Thanks in advance,

Nick

MacPorts - Using the Right Compiler