GnoVM or AVL bug

loadpkg gno.land/p/demo/avl
loadpkg gno.land/p/demo/ufmt

loadpkg gno.land/r/demo/pointerissue $WORK

gnoland start

## Add post
gnokey maketx call -pkgpath gno.land/r/demo/pointerissue -func AddPost -args "key1" -args "test" -args 1 -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1

## Remove post
gnokey maketx call -pkgpath gno.land/r/demo/pointerissue -func RemovePost -args "key1" -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1

## Add identical post again
gnokey maketx call -pkgpath gno.land/r/demo/pointerissue -func AddPost -args "key1" -args "test" -args 1 -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1

-- pointerissue.gno --
package pointerissue

import (
  "gno.land/p/demo/avl"
  "gno.land/p/demo/ufmt"
  "time"
)

type Post struct {
  a string
  b int
  t time.Time
}

var tree1 *avl.Tree
var tree2 *avl.Tree

func init() {
    tree1 = avl.NewTree()
    tree2 = avl.NewTree()
}

func AddPost(key, a string, b int) {
  now := time.Now()

  post := &Post{
    a: a,
    b: b,
    t: now,
  }

  tree1.Set(key, post)
  tree2.Set(key, post)
}

func RemovePost(key string) {
  _, _ = tree1.Remove(key)
  _, _ = tree2.Remove(key)
}

func Render(path string) string {
  i := 0
  output:= ""
  tree1.ReverseIterate("", "", func(key string, value interface{}) bool {
		p := value.(*Post)
		output += ufmt.Sprintf("a: %s, b: %d, t: %s", p.a, p.b, p.t.Format("02 Jan 2006"))
		i++
		return true
	})

	return output
}