Problem with dot position with polyphonic notes

[Jefferson dos Santos Felix]

I have a problem with dot position when I use polyphonic voices, as below:

%% this code generate a dot collision on first compass
\relative
{
     \stemUp
     <<c'4.\\{bes8 a g}>> <e' c>8 <f c a>2
      <<d4.\\{c8 bes a}>> g8 <a f>2
 }

Note, in this example, that the collision occours when the dotted note 
is on spaces.

I have engraved this example on Lilypond 2.3.13, and I don't know if 
this bug has fixed.


Jeff