C and C++ have safety certified implementations available for certain platforms from proprietary vendors. The language itself isn't, and neither are Clang or GCC upstream versions. In addition to the compiler, writing safety certified C or C++ code requires external tooling for static analysis etc. And lots of paper work to show due diligence with tools, processes and testing.

I can tell from $WORK experience that writing safety certified C or C++ code is very expensive and not fun.

For my line of work (systems programming for automotive industry), using Rust would be a massive improvement over C or C++. The amount of undefined behavior pitfalls and footguns is a big hindrance to productivity.

Perhaps the most labour intensive part is dealing with integer overflows in a way that keeps static analysis tooling happy. Just the fact that Rust has well defined semantics for overflows would save so much time and money.

Alas, using Rust was not a viable option when the project(s) I work with were started.