Function assert_no_aliases 

#[doc(hidden)]
pub unsafe fn assert_no_aliases<const N: usize>(
    args: [(SEXP, &str); N],
    borrows: [Option<NativeBorrow>; N],
)

Reject every conflicting argument pair before any Rust borrow is constructed.

Safety

Run on R’s main thread inside an R unwind-protected wrapper. Argument SEXPs must stay reachable for the whole call. Metadata must describe the actual conversions of the corresponding arguments.