Rust and C++ are both high-performance systems programming languages, but they differ significantly in their approach to performance and safety.

Performance

• Similarity in Performance: Both Rust and C++ are highly efficient and often show similar performance in benchmarks. C++ sometimes has an edge due to its maturity and specific optimizations, but Rust's zero-cost abstractions allow it to maintain comparable performance without sacrificing safety.

• Benchmark Variability: In some benchmarks, Rust outperforms C++, while in others, C++ is faster. For example, Rust has been faster in tasks like reverse-complement and binary-trees, but slower in n-body simulations.

• Compile Time: Rust generally has slower compile times due to its more complex safety checks, whereas C++ compilation can be faster but may require additional safety features.

Safety

• Memory Safety: Rust is designed with memory safety in mind, using an ownership and borrowing model to prevent common errors like null pointer dereferences and data races. This makes Rust inherently safer than C++, which relies on manual memory management and can lead to memory leaks or segmentation faults if not handled correctly.

• Concurrency Safety: Rust provides safer concurrency primitives, making it easier to write concurrent code without data races. In contrast, C++ requires manual management of thread safety, which can be error-prone.

• Unsafe Code: Rust allows developers to opt into unsafe code blocks when necessary, providing a clear distinction between safe and unsafe code. C++ does not have this distinction by default, though safety features can be enabled optionally.

In summary, Rust offers superior safety features without significantly compromising performance compared to C++. While C++ may have an edge in certain performance scenarios, Rust's safety guarantees make it an attractive choice for modern systems programming.