Missing terminator inside if-else branch

[raffopazzo]

The following program generates invalid LLVM IR because a terminator is not emitted to jump out of the if-branch.

extern puts(cstr_t) -> i32_t;
func maybe_print_hello(bool_t x) mutable -> i32_t
{
    if (x)
        puts("hello");
    return 0;
}

The IR generated currently is something like

declare signext i32 @puts(i8* nonnull)
define signext i32 @maybe_print_hello(i1 zeroext %x) {
entry:
  br i1 %x, label %then, label %else

then:
  %0 = call i32 @puts(...)

else:
  br label %next

next:
  ret i32 0
}