With LLVM/Clang offering a great diagnostics experience, GCC developers have been challenged to improve the diagnostics and debugging abilities within their open-source compiler. Introduced with GCC 4.8 were improved diagnostics thanks to the Clang competition and it looks like GCC 4.9 will continue trying to enhance the support for the long-standing Free Software Foundation compiler.
One of the new GCC 4.9 features is support for colorizing GCC diagnostic. There's a new -fdiagnostics-color=auto compiler switch to enable colored outputs to terminals. There's also a GCC_COLORS environment variable to achieve the same effect while also being able to customize the coloring.
The colored diagnostics include prettying the error/warning/note markers, caret line, location information, and quoted strings.
More details on the new GCC color options to be introduced in GCC 4.9 can be found from the online documentation.