I'm disappointed by the idea that something is semantic nonsense, but it's okay to do it anyway. The right line of code isn't "return usize::MAX", but "abort()". (I'd also accept "__builtin_unreachable()".)
In general, if a program enters an impossible state, you need to stop running the program, not do something you know is wrong just so the program keeps working a while longer. That's why strcpy_s is much better than strlcpy.
It's also really not fair to compare the legibility of Rust to the legibility of musl: whatever its other merits, musl is written in that old-school C style that makes one imagine that programs run faster when variable names are shorter and braces are omitted.
In general, if a program enters an impossible state, you need to stop running the program, not do something you know is wrong just so the program keeps working a while longer. That's why strcpy_s is much better than strlcpy.
It's also really not fair to compare the legibility of Rust to the legibility of musl: whatever its other merits, musl is written in that old-school C style that makes one imagine that programs run faster when variable names are shorter and braces are omitted.