I compiled a modified version of the demo appsrc on windows with 'go build' that generated the appsrc.exe.
Running the apprsrc.exe actually results in an immediate crash of the application.

And then I tried integrating directly into my own program, the similar problem exists. What could potentially be the problem here?

Recently gstreamer is upgraded to 1.20.0 by brew of mac x86 notebook.
After upgrade, the examples do not work as follows.
In gstreamer 1.18.5, they work well.

[ GSTREAMER ] shim init
[ GST ] program is linked against GStreamer 1.20.0
panic: pipeline error

goroutine 1 [running]:
main.main()
/Users/stoney/coding/go/src/github.com/notedit/gst-go-demo/appsrc/main.go:15 +0x198
exit status 2

https://gstreamer.freedesktop.org/documentation/webrtc/index.html?gi-language=c

Code snippet:
//Want to transcode Incomming RTP packet in mulaw codec (PCMU)
//What I am trying to achieve is push on appsrc and pull it on appsink
package main

import (
"fmt"
"time"
"reflect"
"github.com/notedit/gst"
)

func main() {

pipeline, err := gst.ParseLaunch("appsrc name=mysource ! queue ! appsink name=mysink")

if err != nil {
	panic("pipeline error")
}

element := pipeline.GetByName("mysource")
sink := pipeline.GetByName("mysink")

pipeline.SetState(gst.StatePlaying)
fmt.Println(reflect.TypeOf(sink))


go func(element *gst.Element) {
i:=0
for {

		if i > 100 {
			break
		}

		data := make([]byte, 320*240*3)

		err := element.PushBuffer(data)

		if err != nil {
			fmt.Println("push buffer error")
			break
		}

		fmt.Println("push one")
		i++
		time.Sleep(50000000)
	}
}(element)


	for {
		sample, err := sink.PullSample()
		if err != nil {
			if element.IsEOS() == true {
				fmt.Println("eos")
				break
			} else {
				fmt.Println(err)
				continue
			}
		}
		fmt.Println("got sample", sample.Duration)
	}

pipeline.SetState(gst.StateNull)

pipeline = nil
element = nil
//videoCap = nil

}

Error:
It thowing error as:
** (main:9358): CRITICAL **: 02:47:33.320: gst_app_sink_is_eos: assertion 'GST_IS_APP_SINK (appsink)' failed
could not pull a sample from appsink

-> sink receives 'eos' as it starts

suggest or help pls????
Thanks in advance...