From: Russ Cox <rsc@golang.org>
Date: Sat, 22 Dec 2012 21:45:35 +0000 (-0500)
Subject: cmd/yacc: fix debug print of token name
X-Git-Tag: go1.1rc2~1544
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=b3bb4bd2925bc6715e5c91175021a2386f4017bb;p=gostls13.git

cmd/yacc: fix debug print of token name

The array skips the first TOKSTART entries.

Fixes #4410.

R=golang-dev, ken2, ken
CC=golang-dev
https://golang.org/cl/6999054
---

diff --git a/src/cmd/yacc/units.y b/src/cmd/yacc/units.y
index 00ccaf2ece..9c1b0b3364 100644
--- a/src/cmd/yacc/units.y
+++ b/src/cmd/yacc/units.y
@@ -11,6 +11,11 @@
 
 %{
 
+// This tag will end up in the generated y.go, so that forgetting
+// 'make clean' does not fail the next build.
+
+// +build ignore
+
 // units.y
 // example of a Go yacc program
 // usage is
diff --git a/src/cmd/yacc/yacc.go b/src/cmd/yacc/yacc.go
index 62655e7cd2..0c18f93b6c 100644
--- a/src/cmd/yacc/yacc.go
+++ b/src/cmd/yacc/yacc.go
@@ -3228,9 +3228,10 @@ type $$Lexer interface {
 const $$Flag = -1000
 
 func $$Tokname(c int) string {
-	if c > 0 && c <= len($$Toknames) {
-		if $$Toknames[c-1] != "" {
-			return $$Toknames[c-1]
+	// 4 is TOKSTART above
+	if c >= 4 && c-4 < len($$Toknames) {
+		if $$Toknames[c-4] != "" {
+			return $$Toknames[c-4]
 		}
 	}
 	return __yyfmt__.Sprintf("tok-%v", c)