From cefbf4d7b57975a7d0e247e2bf3effaf4ec47333 Mon Sep 17 00:00:00 2001
From: Robert Bartlensky <bartlensky.robert@gmail.com>
Date: Thu, 1 Aug 2019 21:07:47 +0100
Subject: [PATCH] Allow trailing comma in macro 2.0 declarations.

---
 src/libsyntax/ext/tt/macro_rules.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/libsyntax/ext/tt/macro_rules.rs b/src/libsyntax/ext/tt/macro_rules.rs
index 2a2df76d30c..81c5ef135b2 100644
--- a/src/libsyntax/ext/tt/macro_rules.rs
+++ b/src/libsyntax/ext/tt/macro_rules.rs
@@ -282,7 +282,10 @@ pub fn compile(
         quoted::TokenTree::Sequence(
             DelimSpan::dummy(),
             Lrc::new(quoted::SequenceRepetition {
-                tts: vec![quoted::TokenTree::token(token::Semi, def.span)],
+                tts: vec![quoted::TokenTree::token(
+                    if body.legacy { token::Semi } else { token::Comma },
+                    def.span,
+                )],
                 separator: None,
                 kleene: quoted::KleeneToken::new(quoted::KleeneOp::ZeroOrMore, def.span),
                 num_captures: 0,