line break also breaks crescendo

[Andrew Hawryluk]

I think this is a bug. I expect my code to produce two crescendo
marks, but the second one doesn't appear.

\version "2.11.36"
\paper {ragged-right = ##t}
\relative c'' { c1\< R1\! c1\< \break R1\! }

invoking LilyPond produces a programming error:
cresctobreak.ly:6:20: warning: programming error: Spanner `Hairpin' is
not fully contained in parent spanner. Ignoring orphaned part
        c1\< R1\! c1
                    \< \break R1\!

Cheers,
Andrew Hawryluk