Tabs for indentation, spaces for alignment. This is the only sane standard.

I still find it discomforting that it mandates the use of tabs in the middle of the line -

  void<tab>function(int);

A cleaner option is "tabs for indentation, spaces for alignment", but with tabs allowed at the beginning of line only. This way opening a file in an editor with a different tab size will still preserve the alignment of the parts.