Giving C a superpower: custom header file (safe_c.h)

Intentionally or not, this post demonstrates one of the things that makes safer abstractions in C less desirable: the shared pointer implementation uses a POSIX mutex, which means it’s (1) not cross platform, and (2) pays the mutex overhead even in provably single-threaded contexts. In other words, it’s not a zero-cost abstraction.

C++’s shared pointer has the same problem; Rust avoids it by having two types (Rc and Arc) that the developer can select from (and which the compiler will prevent you from using unsafely).

I'd think a POSIX mutex--a standard API that I not only could implement anywhere, but which has already been implemented all over the place--is way more "cross platform" than use of atomics.