golang syscall_linux_amd64_gc 代码
文件路径：/src/cmd/vendor/golang.org/x/sys/unix/syscall_linux_amd64_gc.go
/ Copyright 2016 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 amd64 && linux && gc
/ +build amd64,linux,gc
package unix
import "syscall"
/go:noescape
func gettimeofday(tv *Timeval) (err syscall.Errno)