lol. A functions module system that’s easy to use and adopted? A package manager? A well implemented hash table? Fast compile times? Effectively no segfaults? Effectively no memory leaks? Comparatively no race condition bugs? A benchmark and unit test framework baked into the language? Auto optimization of the layout of structs? No UB?
I don’t know what you’re counting as “3% of the issues” but if those are the 3%, they sound like massive productivity and safety wins that’s not existed in a language with a similar performance profile to C/C++.
Different (though related) things make compiling Rust slow. In both cases the compiler can spend a lot of time working on types which you, as programmer, weren't really thinking about. Rust cares about types which could exist based on what you wrote but which you never made, whereas C++ doesn't care about that, but it does need to do a lot of "from scratch" work for parametrised types that Rust doesn't have to because C++ basically does a lot of textual substitution in template expansion rather than "really" having parametrised typing.
If you're comparing Clang the backend optimiser work is identical in both cases it's LLVM.
People who've never measured often believe Rust's borrowck needs a lot of compiler effort but actual measurements don't agree - it's not free but it's very cheap (in terms of proportion of compiler runtime).
For most day to day cases, rust will actually compile faster because the build system will do good incremental builds - not perfect, but better than c++. Also clean builds are still “perfectly” parallelized by default.
And yes, while rust has a reputation for being slow, in my experience it’s faster for most projects you encounter in practice because the c++ ecosystem is generally not parallelized and even if it is many projects have poor header hygiene that makes things slow.
I don’t know what you’re counting as “3% of the issues” but if those are the 3%, they sound like massive productivity and safety wins that’s not existed in a language with a similar performance profile to C/C++.