From: Alan Donovan <adonovan@google.com>
Date: Wed, 22 Jun 2016 14:41:30 +0000 (-0400)
Subject: cmd/vet/internal/cfg: don't crash on malformed goto statement
X-Git-Tag: go1.7rc1~69
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=4764d6fd6e64d9d40e7131a3bf4ea0eb1507ef1f;p=gostls13.git

cmd/vet/internal/cfg: don't crash on malformed goto statement

Change-Id: Ib285c02e240f02e9d5511bd448163ec1d4e75516
Reviewed-on: https://go-review.googlesource.com/24323
Reviewed-by: Rob Pike <r@golang.org>
---

diff --git a/src/cmd/vet/internal/cfg/builder.go b/src/cmd/vet/internal/cfg/builder.go
index 79c906bca0..da1cc7e638 100644
--- a/src/cmd/vet/internal/cfg/builder.go
+++ b/src/cmd/vet/internal/cfg/builder.go
@@ -98,7 +98,9 @@ start:
 			}
 
 		case token.GOTO:
-			block = b.labeledBlock(s.Label)._goto
+			if s.Label != nil {
+				block = b.labeledBlock(s.Label)._goto
+			}
 		}
 		if block == nil {
 			block = b.newBlock("undefined.branch")
diff --git a/src/cmd/vet/internal/cfg/cfg_test.go b/src/cmd/vet/internal/cfg/cfg_test.go
index 5d98f136bd..2400fed6f4 100644
--- a/src/cmd/vet/internal/cfg/cfg_test.go
+++ b/src/cmd/vet/internal/cfg/cfg_test.go
@@ -122,6 +122,12 @@ func f10(ch chan int) {
 	}
 	live()
 }
+
+func f11() {
+	goto; // mustn't crash
+	dead()
+}
+
 `
 
 func TestDeadCode(t *testing.T) {