使用-buildmode = shared和-linkshared标志减少Go中的插件（.so）大小

I would like to reduce the size of the plugin (.so file) by removing common symbols used in both the plugin and the main program, e.g. go runtime and standard library.

Here is my test project.

main.go:

package main

import (
    "fmt"
    "os"
    "plugin"
)

type Plugin interface {
    SayHello()
    SayGoodbye()
}

func main() {
    if len(os.Args) < 2 {
        fmt.Fprintf(os.Stderr, "Usage: %s <plugin.so>
", os.Args[0])
        os.Exit(1)
    }

    p, err := plugin.Open(os.Args[1])
    if err != nil {
        fmt.Fprintf(os.Stderr, "plugin.Open: %v
", err)
        os.Exit(1)
    }

    piTemp, err := p.Lookup("Plugin")
    if err != nil {
        fmt.Fprintf(os.Stderr, "plugin.Open: %v
", err)
        os.Exit(1)
    }

    pi, ok := piTemp.(Plugin)
    if !ok {
        fmt.Fprintf(os.Stderr, "Unable to cast helloTemp to Plugin interface
")
        os.Exit(1)
    }

    pi.SayHello()
    pi.SayGoodbye()
}

plugin/plugin.go:

package main

import "fmt"

type PluginImpl struct {}

var Plugin PluginImpl

func (pi *PluginImpl) SayHello() {
    fmt.Printf("Hello from the plugin!
")
}

func (pi *PluginImpl) SayGoodbye() {
    fmt.Printf("Goodbye from the plugin!
")
}

build.sh:

#!/bin/sh

set -e

go clean ./...
go build
cd plugin
go build -buildmode=plugin

Usage example:

$ ./plugins-test ./plugin/plugin.so
Hello from the plugin!
Goodbye from the plugin!

I tried to follow the steps from this article and here what I got:

$ go install -buildmode=shared std
$ go install -buildmode=shared -linkshared go-sandbox/plugins-test
panic: runtime error: index out of range

goroutine 1 [running]:
cmd/go/internal/work.(*Builder).linkSharedAction.func2(0x84607e0)
    /usr/local/go/src/cmd/go/internal/work/action.go:745 +0x7dd
cmd/go/internal/work.(*Builder).cacheAction(0x8d7cfc0, 0x90fdd00, 0x14, 0x0, 0x8efc740, 0x90fdd00)
    /usr/local/go/src/cmd/go/internal/work/action.go:314 +0x84
cmd/go/internal/work.(*Builder).linkSharedAction(0x8d7cfc0, 0x1, 0x1, 0x8e2373a, 0x6, 0x8eec840, 0x8e2373a)
    /usr/local/go/src/cmd/go/internal/work/action.go:738 +0x201
cmd/go/internal/work.(*Builder).buildmodeShared(0x8d7cfc0, 0x1, 0x1, 0x8c18050, 0x1, 0x2, 0x0, 0x0, 0x0, 0x8eec840, ...)
    /usr/local/go/src/cmd/go/internal/work/action.go:649 +0xe8
cmd/go/internal/work.InstallPackages(0x8c18050, 0x1, 0x2, 0x0, 0x0, 0x0)
    /usr/local/go/src/cmd/go/internal/work/build.go:503 +0xb9c
cmd/go/internal/work.runInstall(0x884ae20, 0x8c18050, 0x1, 0x2)
    /usr/local/go/src/cmd/go/internal/work/build.go:417 +0x52
main.main()
    /usr/local/go/src/cmd/go/main.go:219 +0x8a4

The behavior is the same on go1.11.2 linux/386 and go1.11.2 linux/arm. On MacOS the feature seems to be missing --- -buildmode=shared not supported on darwin/amd64.

Am I doing something wrong or this feature is a little bit broken?