//@ force-host //@ no-prefer-dynamic #![crate_type = "proc-macro"] extern crate proc_macro; use proc_macro::*; #[proc_macro_derive(NoMarker)] pub fn f(input: TokenStream) -> TokenStream { if input.to_string().contains("rustc_copy_clone_marker") { panic!("found `#[rustc_copy_clone_marker]`"); } TokenStream::new() }