goleak in the syscall.Syscall

[hawkingrei]

Bug Report

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3. What did you see instead (Required)

goleak: Errors on successful test run: found unexpected goroutines:
[Goroutine 5 in state syscall, with syscall.Syscall on top of the stack:
syscall.Syscall(0x538becb?, 0x0?, 0xa80?, 0x21167a0?)
	GOROOT/src/syscall/syscall_linux.go:69 +0x25
syscall.Close(0xc000142560?)
	GOROOT/src/syscall/zsyscall_linux_amd64.go:320 +0x25
internal/poll.(*SysFile).destroy(...)
	GOROOT/src/internal/poll/fd_unixjs.go:24
internal/poll.(*FD).destroy(0xc001446060)
	GOROOT/src/internal/poll/fd_unix.go:81 +0x51
internal/poll.(*FD).decref(0x7f6735c8ac00?)
	GOROOT/src/internal/poll/fd_mutex.go:213 +0x53
internal/poll.(*FD).Close(0xc001446060)
	GOROOT/src/internal/poll/fd_unix.go:104 +0x45
os.(*file).close(0xc001446060)
	GOROOT/src/os/file_unix.go:315 +0x98
]
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