runtime error: invalid memory address or nil pointer dereference

[Shagrat2]

Failed to continue - runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation]
Unable to propogate EXC_BAD_ACCESS signal to target process and panic (see https://github.com/go-delve/delve/issues/852)
Last known immediate stacktrace (goroutine id 3628):
	?:-1
		<unknown>
	/usr/local/go/src/runtime/asm_amd64.s:655
		runtime.asmcgocall
	?:-1
		<unknown>
	/usr/local/go/src/syscall/zsyscall_darwin_amd64.go:240
		syscall.sendto
	/usr/local/go/src/syscall/syscall_unix.go:287
		syscall.Sendto
	/usr/local/go/src/internal/poll/fd_unix.go:330
		internal/poll.(*FD).WriteTo
	/usr/local/go/src/net/fd_unix.go:226
		net.(*netFD).writeTo
	/usr/local/go/src/net/udpsock_posix.go:80
		net.(*UDPConn).writeTo
	/usr/local/go/src/net/udpsock.go:170
		net.(*UDPConn).WriteTo
	/Users/ivan/workspace/golang/src/golang.org/x/net/icmp/endpoint.go:69
		golang.org/x/net/icmp.(*PacketConn).WriteTo
	/Users/ivan/workspace/golang/src/github.com/tatsushid/go-fastping/fastping.go:537
		github.com/tatsushid/go-fastping.(*Pinger).sendICMP.func1
	/usr/local/go/src/runtime/asm_amd64.s:1357
		runtime.goexit