Can you explain why abstraction is bad? Abstraction does _not_ mean your program will be slower. In fact, the opposite can happen, because the compiler has more context to work with, and can get rid of stuff.

Haskell + stream fusion gives better results than well tuned C in some very typical situations http://research.microsoft.com/en-us/um/people/simonpj/papers...

Even just comparing C++/C, C++'s templating mechanisms mean that generic containers can be optimised on a per-type basis.

Abstraction and overhead are not as tightly coupled as they used to be, and not introducing Heartbleed-style bugs is worth a lot in my opinion