1 // +build !nacl 2 // run 3 4 // Copyright 2015 The Go Authors. All rights reserved. 5 // Use of this source code is governed by a BSD-style 6 // license that can be found in the LICENSE file. 7 8 // Issue 11771: Magic comments should ignore carriage returns. 9 10 package main 11 12 import ( 13 "bytes" 14 "fmt" 15 "io/ioutil" 16 "log" 17 "os" 18 "os/exec" 19 "path/filepath" 20 "runtime" 21 ) 22 23 func main() { 24 if runtime.Compiler != "gc" { 25 return 26 } 27 28 dir, err := ioutil.TempDir("", "go-issue11771") 29 if err != nil { 30 log.Fatalf("creating temp dir: %v\n", err) 31 } 32 defer os.RemoveAll(dir) 33 34 // The go:nowritebarrier magic comment is only permitted in 35 // the runtime package. So we confirm that the compilation 36 // fails. 37 38 var buf bytes.Buffer 39 fmt.Fprintln(&buf, ` 40 package main 41 42 func main() { 43 } 44 `) 45 fmt.Fprintln(&buf, "//go:nowritebarrier\r") 46 fmt.Fprintln(&buf, ` 47 func x() { 48 } 49 `) 50 51 if err := ioutil.WriteFile(filepath.Join(dir, "x.go"), buf.Bytes(), 0666); err != nil { 52 log.Fatal(err) 53 } 54 55 cmd := exec.Command("go", "tool", "compile", "x.go") 56 cmd.Dir = dir 57 output, err := cmd.CombinedOutput() 58 if err == nil { 59 log.Fatal("compile succeeded unexpectedly") 60 } 61 if !bytes.Contains(output, []byte("only allowed in runtime")) { 62 log.Fatalf("wrong error message from compiler; got:\n%s\n", output) 63 } 64 } 65
