They’re exceptions because Lisp programmers are rarely looking to match the inherent unsafety of C by removing heap allocation, bounds checks, type checks, over

They’re exceptions because Lisp programmers are rarely looking to match the inherent unsafety of C by removing heap allocation, bounds checks, type checks, overflow checks, and so on. For many programmers, those are valuable features, something not reflected in the average C program. Eliminating those—much of which is an exercise in declaring what you believe are facts to the compiler—is not difficult, and it’s not hard to produce assembly rather close to that of a usual C compiler.