From: Ken Thompson <ken@golang.org>
Date: Fri, 3 Apr 2009 01:06:43 +0000 (-0700)
Subject: compiler falut for forgetting
X-Git-Tag: weekly.2009-11-06~1903
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=9efd6b8a3d4d9b8336abf37d63487aded193b8b2;p=gostls13.git

compiler falut for forgetting
the assignment on a type switch

R=r
OCL=27048
CL=27048
---

diff --git a/src/cmd/gc/swt.c b/src/cmd/gc/swt.c
index 70d1a9e477..263496701f 100644
--- a/src/cmd/gc/swt.c
+++ b/src/cmd/gc/swt.c
@@ -763,6 +763,13 @@ typeswitch(Node *sw)
 	Case *c, *c0, *c1;
 	int ncase;
 
+	if(sw->ntest == nil)
+		return;
+	if(sw->ntest->right == nil) {
+		setlineno(sw);
+		yyerror("type switch must have an assignment");
+		return;
+	}
 	walktype(sw->ntest->right, Erv);
 	if(!istype(sw->ntest->right->type, TINTER)) {
 		yyerror("type switch must be on an interface");