test: match gccgo error messages for label.go and label1.go.

label.go:30:1: error: label ‘L6’ already defined
label.go:28:1: note: previous definition of ‘L6’ was here
label.go:23:1: error: label ‘L4’ defined and not used
label.go:52:2: error: label ‘defalt’ defined and not used
label.go:17:1: error: label ‘L2’ defined and not used
label.go:26:1: error: label ‘L5’ defined and not used
label.go:20:1: error: label ‘L3’ defined and not used
label.go:14:1: error: label ‘L1’ defined and not used

label1.go:32:13: error: invalid continue label ‘L2’
label1.go:44:13: error: invalid continue label ‘L3’
label1.go:52:10: error: invalid break label ‘L4’
label1.go:55:13: error: invalid continue label ‘L4’
label1.go:65:9: error: invalid break label ‘L5’
label1.go:68:12: error: invalid continue label ‘L5’
label1.go:76:10: error: invalid break label ‘L1’
label1.go:79:13: error: invalid continue label ‘L1’

R=rsc
CC=golang-dev
https://golang.org/cl/4275078

test/label.go

@@ -11,23 +11,23 @@ package main
 var x int
 
 func f() {
-L1: // ERROR "label L1 defined and not used"
+L1: // ERROR "label .*L1.* defined and not used"
 	for {
 	}
-L2: // ERROR "label L2 defined and not used"
+L2: // ERROR "label .*L2.* defined and not used"
 	select {
 	}
-L3: // ERROR "label L3 defined and not used"
+L3: // ERROR "label .*L3.* defined and not used"
 	switch {
 	}
-L4: // ERROR "label L4 defined and not used"
+L4: // ERROR "label .*L4.* defined and not used"
 	if true {
 	}
-L5: // ERROR "label L5 defined and not used"
+L5: // ERROR "label .*L5.* defined and not used"
 	f()
-L6:
+L6: // GCCGO_ERROR "previous"
 	f()
-L6: // ERROR "label L6 already defined at"
+L6: // ERROR "label .*L6.* already defined"
 	f()
 	if x == 20 {
 		goto L6
@@ -49,7 +49,7 @@ L9:
 	switch {
 	case true:
 		break L9
-	defalt: // ERROR "label defalt defined and not used"
+	defalt: // ERROR "label .*defalt.* defined and not used"
 	}
 
 L10:

test/label1.go

@@ -29,7 +29,7 @@ L2:
 			break L2
 		}
 		if x == 1 {
-			continue L2 // ERROR "invalid continue label L2"
+			continue L2 // ERROR "invalid continue label .*L2"
 		}
 		goto L2
 	}
@@ -41,7 +41,7 @@ L3:
 			break L3
 		}
 		if x == 12 {
-			continue L3 // ERROR "invalid continue label L3"
+			continue L3 // ERROR "invalid continue label .*L3"
 		}
 		goto L3
 	}
@@ -49,10 +49,10 @@ L3:
 L4:
 	if true {
 		if x == 13 {
-			break L4 // ERROR "invalid break label L4"
+			break L4 // ERROR "invalid break label .*L4"
 		}
 		if x == 14 {
-			continue L4 // ERROR "invalid continue label L4"
+			continue L4 // ERROR "invalid continue label .*L4"
 		}
 		if x == 15 {
 			goto L4
@@ -62,10 +62,10 @@ L4:
 L5:
 	f()
 	if x == 16 {
-		break L5 // ERROR "invalid break label L5"
+		break L5 // ERROR "invalid break label .*L5"
 	}
 	if x == 17 {
-		continue L5 // ERROR "invalid continue label L5"
+		continue L5 // ERROR "invalid continue label .*L5"
 	}
 	if x == 18 {
 		goto L5
@@ -73,10 +73,10 @@ L5:
 
 	for {
 		if x == 19 {
-			break L1 // ERROR "invalid break label L1"
+			break L1 // ERROR "invalid break label .*L1"
 		}
 		if x == 20 {
-			continue L1 // ERROR "invalid continue label L1"
+			continue L1 // ERROR "invalid continue label .*L1"
 		}
 		if x == 21 {
 			goto L1