What makes virtual functions so slow? C++

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Virtual functions and performance - C++

I'm trying to refactor my code, and everywhere people say that using virtual functions is a huuuuge nono performance-wise, why? and is there another way that I can inherit a class and redefine functions that are defined in the base class?

Answer 1

A good reference article for this topic can be found here: http://coldattic.info/shvedsky/pro/blogs/a-foo-walks-into-a-bar/posts/3

For the lazy, I guess the answer is "maybe slower slightly"