I want to set some warning settings for my GCC compiler in Xcode (using GCC4.2), but I am unable to find a section in my Xcode build settings which lists the Warnings settings. Any idea?

For example, I am not seeing the screeshot posted in the answer for this post:
[Debugging exception thrown in Objective C and XCode](https://stackoverflow.com/questions/711650/xcode-and-iphone-compiler-warning)