| // Copyright 2015 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| //go:build go1.5 |
| // +build go1.5 |
| |
| package driver |
| |
| import ( |
| "flag" |
| "fmt" |
| "os" |
| "runtime/trace" |
| ) |
| |
| var traceFile = flag.String("trace", "", "write an execution trace to the named file after execution") |
| |
| func startTraceGo15() func() { |
| // New runtime tracing added in Go 1.5. |
| if *traceFile != "" { |
| f, err := os.Create(*traceFile) |
| if err != nil { |
| fmt.Fprintln(os.Stderr, err) |
| os.Exit(1) |
| } |
| if err := trace.Start(f); err != nil { |
| fmt.Fprintf(os.Stderr, "can't start tracing: %s\n", err) |
| os.Exit(1) |
| } |
| |
| return func() { |
| trace.Stop() |
| f.Close() |
| } |
| } |
| return func() {} |
| } |
| |
| func init() { |
| startTrace = startTraceGo15 |
| } |