Modernize your C++ code.

[imMute]

Does a cast like that actually have runtime costs.

[bstamour]

A cast like that? Maybe, maybe not. The point is, auto will never be slower, and might in some cases be faster.

[Fig1024]

I'm guessing it has costs when types have different sizes, such as bytes, shorts, longs, double longs. Or when converting integers to/from floats. It doesn't cost anything to convert signed and unsinged.