Trouble with trill spanner avoiding slur

[Knute Snortum]

In this example...

%%% Start

\version "2.19.81"

\language "english"

{

  \override TrillSpanner.avoid-slur = #'inside

  \override TrillSpanner.outside-staff-priority = ##f

  c''1( | c''2. \startTrillSpan c''4 \stopTrillSpan | c''1) |

}

%%% End

...the slur doesn't avoid the trill spanner.  Do I need to adjust the slur with \shape or is the slur supposed to adjust its position automatically?

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Knute Snortum

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