No I'm not, those new-fangled compilers with that fancy ass "think about performance up front" language doesn't have the umpteen years and billions of dollars worth of research put into it the way C++ has.
The new-generation languages (of which Go is a bad example; Rust and Nimrod, and now Swift, are much better ones) don't attempt to get the computer to do the kind of magic at runtime (garbage collection, type reflection) that made previous-gen languages so slow.
Instead, these NGLs start with the assumption of C/C++ runtime semantics, and then, through extra work done at compile time (e.g. type inference, ownership-tracking) clear away as much implied/redundant/unneeded syntax as possible.
Well it sounds as if it's as simple as being able to take advantage of optimizations to meet or beat C++.
good luck with that.
Also, FYI: Nimrod is garbage collected, which goes counter against your reasoning.
The moment you include dynamic dispatch, auto-conversion to big integers, or one of a zillion of other high-level features without also introducing ways for the programmer to indicate how the compiler should implement them, you give up being just as fast as C/C++.
Yes, the difference may be small, and spending time on improving your compiler can make it smaller and smaller, but for any 'real world program', it won't be zero.
The same is true for C vs assembly, but there, the difference mostly _is_ small because C has none of those high-level features.
Also, few people have the skills and the time to wrote well-optimized C/C++.
I just didn't want to continue a conversation with someone who thinks adjusting the age old "optimizations will eventually make it as fast" to be "compiling to C/C++ as an optimization will eventually make it as fast" was somehow going to magically make it come true.
It's the same old argument reskinned, and as you pointed out, the feature set has a lot to do with it.
Significant difference there.