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Lifetimes in procedural macros aren't being parsed correctly #50942
Description
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`.
Activity
petrochenkov commentedon May 21, 2018
Note the missing
'in "undeclared lifetime namestatic", that's why it's undeclared.petrochenkov commentedon May 21, 2018
Oh crap,
fn gluedoesn'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.petrochenkov commentedon May 21, 2018
Sorry.
alexcrichton commentedon May 21, 2018
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?
petrochenkov commentedon May 21, 2018
It'll happen sooner if you do it.
alexcrichton commentedon May 21, 2018
Ok! I'll take care of this
rustc: Fix procedural macros generating lifetime tokens
alexcrichton commentedon May 21, 2018
I've posted a fix for this at #50946
Rollup merge of rust-lang#50946 - alexcrichton:fix-parse-lifetime, r=…