Memory leak

[vovanmozg]

ruby 3.0.0
libxml-ruby: 3.2.2
libxml: 2.9.10
Debian 11

Demo:

  def test_remove_leak
    doc = LibXML::XML::Document.new('1.0')
    10.times do
      before = `ps -o rss= -p #{Process.pid}`.chop
      GC.start
      100000.times do
        doc.root = LibXML::XML::Node.new('node')
      end
      GC.start
      puts before + ' / ' + `ps -o rss= -p #{Process.pid}`
    end
  end

Output:

25108 / 40276
40276 / 55852
55852 / 71428
71428 / 87268
87268 / 102844
102844 / 118420
118420 / 133996
133996 / 149572
149572 / 165412
165412 / 180988

[vovanmozg]

Demo 2:

  def test_remove_leak
    10.times do
      before = `ps -o rss= -p #{Process.pid}`.chop
      GC.start
      100000.times do
        doc = LibXML::XML::Document.new('1.0')
        doc.root = LibXML::XML::Node.new('node')
        doc.root.remove!
      end
      GC.start
      puts before + ' / ' + `ps -o rss= -p #{Process.pid}`
    end
  end

[cfis]

This was fixed in #180.