In a battle against LLVM/Clang, GCC 4.8 will improve the code diagnostics support to better assist developers in debugging code errors/warnings in a user-friendly manner.
One of the long-advertised features of LLVM’s Clang C/Objective-C/C++ compiler has been that it offers more user-friendly diagnostics than the GNU Compiler Collection. Historically this has been true, especially against GCC 4.2 — the last GPLv2 compiler release. However, GCC developers have been working to improve this situation. With GCC 4.8, it looks like more of this work will come to fruition.