From 247959d9b85be560d71b81e0e44fcf4c9cc900e4 Mon Sep 17 00:00:00 2001
From: Russ Cox <rsc@golang.org>
Date: Wed, 4 Nov 2015 15:28:47 -0500
Subject: [PATCH] cmd/compile: reject identifiers beginning with non-ASCII
 digit

Fixes #11359.

Change-Id: I0fdfa410939f7e42020cbb19d74a67e1cc3cd610
Reviewed-on: https://go-review.googlesource.com/16919
Reviewed-by: Ian Lance Taylor <iant@golang.org>
---
 src/cmd/compile/internal/gc/lex.go |  3 +++
 test/fixedbugs/issue11359.go       | 11 +++++++++++
 2 files changed, 14 insertions(+)
 create mode 100644 test/fixedbugs/issue11359.go

diff --git a/src/cmd/compile/internal/gc/lex.go b/src/cmd/compile/internal/gc/lex.go
index 7fd6a62dbad97..1f468c1dea931 100644
--- a/src/cmd/compile/internal/gc/lex.go
+++ b/src/cmd/compile/internal/gc/lex.go
@@ -1469,6 +1469,9 @@ talph:
 			if !unicode.IsLetter(r) && !unicode.IsDigit(r) && (importpkg == nil || r != 0xb7) {
 				Yyerror("invalid identifier character U+%04x", r)
 			}
+			if cp.Len() == 0 && unicode.IsDigit(r) {
+				Yyerror("identifier cannot begin with digit U+%04x", r)
+			}
 			cp.WriteRune(r)
 		} else if !isAlnum(c) && c != '_' {
 			break
diff --git a/test/fixedbugs/issue11359.go b/test/fixedbugs/issue11359.go
new file mode 100644
index 0000000000000..6ffffede6b972
--- /dev/null
+++ b/test/fixedbugs/issue11359.go
@@ -0,0 +1,11 @@
+// errorcheck
+
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// identifiers beginning with non-ASCII digits were incorrectly accepted.
+// issue 11359.
+
+package p
+var ۶ = 0 // ERROR "identifier cannot begin with digit"