xcode build errors:
Unsupported compiler ‘GCC 4.2’ selected for architecture ‘i386’
This can be caused by importing a project for a pre- iOS 5 SDK into a copy of xcode with iOS 5 SDK only.
To fix, click your Project -> Build Settings. Then under Build Options, there is an entry for Compiler for C/C++/Objective-C. Choose Apple LLVM compiler 3.0.
There is a chance this could effect other aspects of your binaries as you are using a new compiler, so YMMV. That being said, it’s so far caused no issues for me.