1 // errorcheck -0 -live 2 3 // Copyright 2016 The Go Authors. All rights reserved. 4 // Use of this source code is governed by a BSD-style 5 // license that can be found in the LICENSE file. 6 7 // Issue 15747: liveness analysis was marking heap-escaped params live too much, 8 // and worse was using the wrong bitmap bits to do so. 9 10 package p 11 12 var global *[]byte 13 14 type Q struct{} 15 16 type T struct{ M string } 17 18 var b bool 19 20 func f1(q *Q, xx []byte) interface{} { // ERROR "live at call to newobject: xx$" "live at call to writebarrierptr: &xx$" "live at entry to f1: xx$" 21 // xx was copied from the stack to the heap on the previous line: 22 // xx was live for the first two prints but then it switched to &xx 23 // being live. We should not see plain xx again. 24 if b { 25 global = &xx // ERROR "live at call to writebarrierptr: &xx$" 26 } 27 xx, _, err := f2(xx, 5) // ERROR "live at call to f2: &xx$" "live at call to writebarrierptr: err.data err.type$" 28 if err != nil { 29 return err 30 } 31 return nil 32 } 33 34 //go:noinline 35 func f2(d []byte, n int) (odata, res []byte, e interface{}) { // ERROR "live at entry to f2: d$" 36 if n > len(d) { 37 return d, nil, &T{M: "hello"} // ERROR "live at call to newobject: d" "live at call to writebarrierptr: d" 38 } 39 res = d[:n] 40 odata = d[n:] 41 return 42 } 43