src/test/incremental/auxiliary/issue_54059.rs

   1 // Copyright 2018 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 // force-host
  12 // no-prefer-dynamic
  13
  14 // check that having extern "C" functions in a proc macro doesn't crash.
  15
  16 #![crate_type="proc-macro"]
  17 #![allow(non_snake_case)]
  18
  19 extern crate proc_macro;
  20
  21 macro_rules! proc_macro_tokenstream {
  22     () => {
  23         ::proc_macro::TokenStream
  24     };
  25 }
  26
  27 macro_rules! proc_macro_expr_impl {
  28     ($(
  29         $( #[$attr:meta] )*
  30         pub fn $func:ident($input:ident: &str) -> String $body:block
  31     )+) => {
  32         $(
  33             // Parses an input that looks like:
  34             //
  35             // ```
  36             // #[allow(unused)]
  37             // enum ProcMacroHack {
  38             //     Input = (stringify!(ARGS), 0).1,
  39             // }
  40             // ```
  41             $( #[$attr] )*
  42             #[proc_macro_derive($func)]
  43             pub fn $func(input: proc_macro_tokenstream!()) -> proc_macro_tokenstream!() {
  44                 unsafe { rust_dbg_extern_identity_u64(0); }
  45                 panic!()
  46             }
  47         )+
  48     };
  49 }
  50
  51 proc_macro_expr_impl! {
  52     pub fn base2_impl(input: &str) -> String {
  53         panic!()
  54     }
  55 }
  56
  57 #[link(name="rust_test_helpers")]
  58 extern "C" {
  59     pub fn rust_dbg_extern_identity_u64(v: u64) -> u64;
  60 }