test: match gccgo error strings.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/10468043
diff --git a/test/fixedbugs/issue4085a.go b/test/fixedbugs/issue4085a.go
index 8a52b26..089637d 100644
--- a/test/fixedbugs/issue4085a.go
+++ b/test/fixedbugs/issue4085a.go
@@ -9,10 +9,10 @@
 type T []int
 
 func main() {
-	_ = make(T, -1)       // ERROR "negative"
-	_ = make(T, 0.5)       // ERROR "constant 0.5 truncated to integer"
-	_ = make(T, 1.0)       // ok
-	_ = make(T, 1<<63)  // ERROR "len argument too large"
-	_ = make(T, 0, -1)    // ERROR "negative cap"
+	_ = make(T, -1)    // ERROR "negative"
+	_ = make(T, 0.5)   // ERROR "constant 0.5 truncated to integer|non-integer len argument"
+	_ = make(T, 1.0)   // ok
+	_ = make(T, 1<<63) // ERROR "len argument too large"
+	_ = make(T, 0, -1) // ERROR "negative cap"
 	_ = make(T, 10, 0) // ERROR "len larger than cap"
 }