Incorrect reading, potentially garbage in memory

[the-Arioch]

zexmlss.pas(5907,19) Hint: Local variable "fcc" does not seem to be initialized

You confused TStream.Read and TStream.ReadBuffer!

procedure TZEPicture.AssignFromStream(AStream: TStream);
var
  fcc: LongWord;
begin
  if Assigned(FDataStream) then
    FreeAndNil(FDataStream);
  FFileName := '';
  FDataStream := TMemoryStream.Create();
  AStream.Position := 0;
  // detect file type
---  AStream.Read(fcc, SizeOf(fcc));
+++  AStream.ReadBuffer(fcc, SizeOf(fcc));
  if fcc = $474E5089 then
    FFileName := '.png'
  else if fcc = $E0FFD8FF then
    FFileName := '.jpeg';
  AStream.Position := 0;
  FDataStream.CopyFrom(AStream, AStream.Size);
end;