Merge branch 'master' into issue-30961

3 files changed, 8 insertions, 2 deletions

diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 2147e8ec2eb..7b28952aff6 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -237,7 +237,7 @@ pub fn new_parser_from_ts<'a>(sess: &'a ParseSess,
                               cfg: ast::CrateConfig,
                               ts: tokenstream::TokenStream)
                               -> Parser<'a> {
-    tts_to_parser(sess, ts.tts, cfg)
+    tts_to_parser(sess, ts.to_tts(), cfg)
 }
 
 
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 125f1abb062..c143e190c6f 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -258,6 +258,7 @@ pub struct Parser<'a> {
     pub tokens_consumed: usize,
     pub restrictions: Restrictions,
     pub quote_depth: usize, // not (yet) related to the quasiquoter
+    parsing_token_tree: bool,
     pub reader: Box<Reader+'a>,
     /// The set of seen errors about obsolete syntax. Used to suppress
     /// extra detail when the same error is seen twice
@@ -374,6 +375,7 @@ impl<'a> Parser<'a> {
             tokens_consumed: 0,
             restrictions: Restrictions::empty(),
             quote_depth: 0,
+            parsing_token_tree: false,
             obsolete_set: HashSet::new(),
             mod_path_stack: Vec::new(),
             filename: filename,
@@ -2663,7 +2665,7 @@ impl<'a> Parser<'a> {
     }
 
     pub fn check_unknown_macro_variable(&mut self) {
-        if self.quote_depth == 0 {
+        if self.quote_depth == 0 && !self.parsing_token_tree {
             match self.token {
                 token::SubstNt(name) =>
                     self.fatal(&format!("unknown macro variable `{}`", name)).emit(),
@@ -2723,6 +2725,7 @@ impl<'a> Parser<'a> {
                 Err(err)
             },
             token::OpenDelim(delim) => {
+                let parsing_token_tree = ::std::mem::replace(&mut self.parsing_token_tree, true);
                 // The span for beginning of the delimited section
                 let pre_span = self.span;
 
@@ -2787,6 +2790,7 @@ impl<'a> Parser<'a> {
                     _ => {}
                 }
 
+                self.parsing_token_tree = parsing_token_tree;
                 Ok(TokenTree::Delimited(span, Rc::new(Delimited {
                     delim: delim,
                     open_span: open_span,
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index f0a6f8edeec..6fdc9b714d3 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -48,6 +48,8 @@ pub enum DelimToken {
     Bracket,
     /// A curly brace: `{` or `}`
     Brace,
+    /// An empty delimiter
+    NoDelim,
 }
 
 #[derive(Clone, RustcEncodable, RustcDecodable, PartialEq, Eq, Hash, Debug, Copy)]