Even with 4.5 I haven't found the error messages to be nearly as helpful. Also with clang you can easily turn on a way to look for undefined behavior and turn those into warnings/errors which is fantastic and helped me track down a bug BEFORE it caused me huge grief.

> Note that if you're on a Mac, your system's gcc is likely several years out of date.

To be precise: Apple stopped maintaining its GCC branch after the switch to GPL3. The last version available with Apple patches is 4.2.1. There will be no further updates to this branch.

Check out [Colorgcc](http://schlueters.de/colorgcc.html). It helps more than you'd think.