diff --git a/src/cmd/gc/swt.c b/src/cmd/gc/swt.c
index 3f62706f70..3184276365 100644
--- a/src/cmd/gc/swt.c
+++ b/src/cmd/gc/swt.c
@@ -33,6 +33,14 @@ struct	Case
 };
 #define	C	((Case*)nil)
 
+Type*
+notideal(Type *t)
+{
+	if(t != T && t->etype == TIDEAL)
+		return T;
+	return t;
+}
+
 void
 dumpcase(Case *c0)
 {
@@ -254,8 +262,8 @@ sw0(Node *c, Type *place, int arg)
 Type*
 sw1(Node *c, Type *place, int arg)
 {
-	if(place == T)
-		return c->type;
+	if(place != T)
+		return notideal(c->type);
 	return place;
 }
 
@@ -605,7 +613,7 @@ exprswitch(Node *sw)
 	 * walk the cases as appropriate for switch type
 	 */
 	walkcases(sw, sw0, arg);
-	t = sw->ntest->type;
+	t = notideal(sw->ntest->type);
 	if(t == T)
 		t = walkcases(sw, sw1, arg);
 	if(t == T)
diff --git a/test/bugs/bug157.go b/test/bugs/bug157.go
index 207f6bcfdb..9bf68f7a47 100644
--- a/test/bugs/bug157.go
+++ b/test/bugs/bug157.go
@@ -27,6 +27,6 @@ func main() {
 
 
 /*
-bug155.go:20: syntax error near default
-bug155.go:20: first switch statement must be a case
+bug157.go:20: syntax error near default
+bug157.go:20: first switch statement must be a case
 */
diff --git a/test/bugs/bug158.go b/test/fixedbugs/bug158.go
similarity index 86%
rename from test/bugs/bug158.go
rename to test/fixedbugs/bug158.go
index a40bf823a0..cdf3195feb 100644
--- a/test/bugs/bug158.go
+++ b/test/fixedbugs/bug158.go
@@ -22,5 +22,5 @@ func main() {
 
 
 /*
-bug156.go:14: fatal error: dowidth: unknown type: E-33
+bug158.go:14: fatal error: dowidth: unknown type: E-33
 */
diff --git a/test/golden.out b/test/golden.out
index 13c83aa80d..4e7f81552e 100644
--- a/test/golden.out
+++ b/test/golden.out
@@ -109,10 +109,6 @@ bugs/bug157.go:20: syntax error near default
 bugs/bug157.go:20: first switch statement must be a case
 BUG: should compile
 
-=========== bugs/bug158.go
-bugs/bug158.go:14: fatal error: dowidth: unknown type: E-33
-BUG: should compile
-
 =========== fixedbugs/bug016.go
 fixedbugs/bug016.go:7: constant -3 overflows uint