[aengelke]

I'd add code quality as a reason. I find it much easier to understand and modify code in LLVM compared to GCC. Both have a fairly steep learning curve and not too much documentation, but often I (personally) find LLVM's architecture to be more thought out and easier to understand. GCC's age shows in the code base and it feels like many concepts and optimizations are just bolted on without "required" architectural changes for a proper integration.