I just love this one: http://www.viva64.com/en/examples/V504/

  void GlyphComboBox::update(SPFont* spfont)
  {
    if (!spfont) return // <=
  //TODO: figure out why do we need to append("")
  // before clearing items properly...

  //Gtk is refusing to clear the combobox
  //when I comment out this line
    this->append("");
    this->remove_all();
  }

Gee, why do you need the dummy append? It's because you put in so many TODO comments that you concealed the missing semicolon that you otherwise might have found ...

This is arguably not a bug; the developer tested the code, massaged it into working as expected, using what look like well-defined constructs, and documented their surprise at certain aspects of the code, leaving this issue easy to find with a grep for TODO.

On another note, what is surprising here is that they didn't catch it with their compiler. Look, the function returns void. GCC has a diagnostic for this, something like "return with expression in a function returning void". I think that still kicks in even if that expression has void type.