> GC languages (like javascript and Scala) do not have provably (for some value of provably) deterministic execution times This is not unique to GC languages,

> GC languages (like javascript and Scala) do not have provably (for some value of provably) deterministic execution times This is not unique to GC languages, but any languages with dynamic memory management. C++ new/free and STL abstractions built on top are not provably deterministic either. And if you program without ever touching dynamic memory (statically allocating and pooling everything) then GC is not a concern. > I say that to say the zero-cost abstractions of C++ is a huge benefit when writing safety-critical software. You're talking about performance now, not correctness. All those benefits get lost once translated to JS.