From 2a41b31a88356d5a772cb644ab8d29af0bf44742 Mon Sep 17 00:00:00 2001
From: Wang Xuerui <idontknw.wang@gmail.com>
Date: Fri, 29 Jul 2016 16:40:10 +0800
Subject: syntax_ext: format: fix ICE with bad named arguments

---
 src/libsyntax_ext/format.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

(limited to 'src/libsyntax_ext')

diff --git a/src/libsyntax_ext/format.rs b/src/libsyntax_ext/format.rs
index 94bb78edaac..1f6f57c70f7 100644
--- a/src/libsyntax_ext/format.rs
+++ b/src/libsyntax_ext/format.rs
@@ -406,7 +406,9 @@ impl<'a, 'b> Context<'a, 'b> {
                             let arg_idx = match arg_index_consumed.get_mut(i) {
                                 None => 0, // error already emitted elsewhere
                                 Some(offset) => {
-                                    let arg_idx = self.arg_index_map[i][*offset];
+                                    let ref idx_map = self.arg_index_map[i];
+                                    // unwrap_or branch: error already emitted elsewhere
+                                    let arg_idx = *idx_map.get(*offset).unwrap_or(&0);
                                     *offset += 1;
                                     arg_idx
                                 }
-- 
cgit 1.4.1-3-g733a5