<div dir="ltr"><div class="gmail_extra">Indeed! This code need finalize() now because heaptrc detect memory leak:</div><div class="gmail_extra"><br></div><div class="gmail_extra"><div class="gmail_extra">procedure TForm1.Button1Click(Sender: TObject);</div><div class="gmail_extra">var f: TMyRec;</div><div class="gmail_extra">begin</div><div class="gmail_extra">  FillChar(f, SizeOf(TMyRec), 0);</div><div class="gmail_extra">  f.Field1 := 123;</div><div class="gmail_extra">  f.Field2 := 'abc'+IntToStr(f.Field1);</div><div class="gmail_extra">  push(@f);</div><div class="gmail_extra"><br></div><div class="gmail_extra">  system.Finalize(f);</div><div class="gmail_extra"><br></div><div class="gmail_extra">  FillChar(f, SizeOf(TMyRec), 0);</div><div class="gmail_extra">  f.Field1 := 456;</div><div class="gmail_extra">  f.Field2 := 'vbnj'+IntToStr(f.Field1);</div><div class="gmail_extra">  push(@f);</div><div class="gmail_extra">end;</div><div class="gmail_extra"><br></div><div class="gmail_extra">Although, leak is only when FillChar is called again. For example this is not leak:</div><div class="gmail_extra"><br></div><div class="gmail_extra"><div class="gmail_extra">procedure TForm1.Button1Click(Sender: TObject);</div><div class="gmail_extra">var f: TMyRec;</div><div class="gmail_extra">begin</div><div class="gmail_extra">  FillChar(f, SizeOf(TMyRec), 0);</div><div class="gmail_extra">  f.Field1 := 123;</div><div class="gmail_extra">  f.Field2 := 'abc'+IntToStr(f.Field1);</div><div class="gmail_extra">  push(@f);</div><div class="gmail_extra"><br></div><div class="gmail_extra">  f.Field1 := 456;<br></div><div class="gmail_extra">  f.Field2 := 'vbnj'+IntToStr(f.Field1);</div><div class="gmail_extra">  push(@f);</div><div class="gmail_extra"><br></div><div class="gmail_extra"><div class="gmail_extra">  f.Field1 := 789;<br></div><div class="gmail_extra">  f.Field2 := 'zzzz'+IntToStr(f.Field1);</div><div class="gmail_extra">  push(@f);</div></div><div class="gmail_extra">end; </div><div class="gmail_extra"><br></div><div class="gmail_extra">Thanks Olivier for explanation</div></div></div></div>