Lifetimes in procedural macros aren't being parsed correctly

Given this procedural macro:

#![crate_type = "proc-macro"]
#![feature(proc_macro)]

extern crate proc_macro;

use proc_macro::*;

#[proc_macro]
pub fn bar(_input: TokenStream) -> TokenStream {
    let mut ret = Vec::<TokenTree>::new();
    ret.push(Ident::new("static", Span::call_site()).into());
    ret.push(Ident::new("FOO", Span::call_site()).into());
    ret.push(Punct::new(':', Spacing::Alone).into());
    ret.push(Punct::new('&', Spacing::Alone).into());
    ret.push(Punct::new('\'', Spacing::Joint).into());
    ret.push(Ident::new("static", Span::call_site()).into());
    ret.push(Ident::new("i32", Span::call_site()).into());
    ret.push(Punct::new('=', Spacing::Alone).into());
    ret.push(Punct::new('&', Spacing::Alone).into());
    ret.push(Literal::i32_unsuffixed(1).into());
    ret.push(Punct::new(';', Spacing::Alone).into());
    return ret.into_iter().collect()
}

and this invocation:

#![crate_type = "rlib"]
#![feature(proc_macro)]

extern crate bar;

bar::bar!();

we get:

$ rustc +nightly bar.rs
$ rustc +nightly foo.rs -L .
error: lifetimes cannot use keyword names
 --> foo.rs:6:1
  |
6 | bar::bar!();
  | ^^^^^^^^^^^^

error[E0261]: use of undeclared lifetime name `static`
 --> foo.rs:6:1
  |
6 | bar::bar!();
  | ^^^^^^^^^^^^ undeclared lifetime

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0261`.

Note the missing ' in "undeclared lifetime name static", that's why it's undeclared.

Oh crap, fn glue doesn't add ' to the identifier string.
My test with lifetimes in #50473 passed accidentally because all the lifetimes lost their 's so their names were still equal and resolution succeeded.

Sorry.

Aha that'd do it! You found it much faster than I did :)

And no worries! Would you like to send a PR? Or shall I?

It'll happen sooner if you do it.

Ok! I'll take care of this

rustc: Fix procedural macros generating lifetime tokens

I've posted a fix for this at #50946

Rollup merge of rust-lang#50946 - alexcrichton:fix-parse-lifetime, r=…

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Lifetimes in procedural macros aren't being parsed correctly #50942

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Lifetimes in procedural macros aren't being parsed correctly #50942

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petrochenkov commented on May 21, 2018

petrochenkov commented on May 21, 2018

petrochenkov commented on May 21, 2018

alexcrichton commented on May 21, 2018

petrochenkov commented on May 21, 2018

alexcrichton commented on May 21, 2018

alexcrichton commented on May 21, 2018

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