From: Rémy Oudompheng <oudomphe@phare.normalesup.org>
Date: Fri, 21 Sep 2012 19:54:05 +0000 (+1000)
Subject: [release-branch.go1] cmd/gc: avoid an internal error on invalid type switch.
X-Git-Tag: go1.0.3~157
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=705534bd309c8db6b2f616ee29b83dc5483ed4df;p=gostls13.git

[release-branch.go1] cmd/gc: avoid an internal error on invalid type switch.

««« backport 254232c99b3e
cmd/gc: avoid an internal error on invalid type switch.

The error was caused by a call to implements() even when
the type switch variable was not an interface.

Fixes #3786.

R=golang-dev, r
CC=golang-dev, remy
https://golang.org/cl/6354102

»»»
---

diff --git a/src/cmd/gc/swt.c b/src/cmd/gc/swt.c
index f1a95587fd..4079b67da2 100644
--- a/src/cmd/gc/swt.c
+++ b/src/cmd/gc/swt.c
@@ -889,7 +889,7 @@ typecheckswitch(Node *n)
 						yyerror("%lN is not a type", ll->n);
 						// reset to original type
 						ll->n = n->ntest->right;
-					} else if(ll->n->type->etype != TINTER && !implements(ll->n->type, t, &missing, &have, &ptr)) {
+					} else if(ll->n->type->etype != TINTER && t->etype == TINTER && !implements(ll->n->type, t, &missing, &have, &ptr)) {
 						if(have && !missing->broke && !have->broke)
 							yyerror("impossible type switch case: %lN cannot have dynamic type %T"
 								" (wrong type for %S method)\n\thave %S%hT\n\twant %S%hT",