This is a wonderfully written comparison benchmark and it deserves attention even for that reason alone. It knows its target audience, explains what's going on succinctly but completely, and avoids most of the usual benchmark pitfalls that result in comparing apples to oranges. Great job.
The one glaring issue that is ignored is the floating point model used. I understand Rust still doesn't have a usable equivalent to -ffast-math, so I assume it wasn't used for that reason. Some discussion of whether it's permissible in this algorithm (I believe so?) and how much advantage that might give to C++ seems crucial when performance is a priority.
Ironically, reading this has further convinced me that, for all of its disadvantages, I much prefer C++ to Rust for my needs. I'm sure others will draw the opposite conclusion and that's great. Rust is a language that clearly knows what it wants and if your priorities are aligned with that, the performance gap is shrinking and implementation-related reasons to avoid it are rapidly decreasing in number.
The one glaring issue that is ignored is the floating point model used. I understand Rust still doesn't have a usable equivalent to -ffast-math, so I assume it wasn't used for that reason. Some discussion of whether it's permissible in this algorithm (I believe so?) and how much advantage that might give to C++ seems crucial when performance is a priority.
Ironically, reading this has further convinced me that, for all of its disadvantages, I much prefer C++ to Rust for my needs. I'm sure others will draw the opposite conclusion and that's great. Rust is a language that clearly knows what it wants and if your priorities are aligned with that, the performance gap is shrinking and implementation-related reasons to avoid it are rapidly decreasing in number.