Extended first syllable in polysyllabic word

[Joel C. Salomon]

In the example below, the word "Catherine" is to be pronounced
"Ca-a-th'rine ", extending the first syllable over two (unslurred)
notes, and the last two syllables combine on the third note. (I.e.,
*not* "Cath-er-ine".)

It would seem that they way I wrote it below, "Cath _ -- erine",
*should* work, but this gives an error:

    programming error: hyphen not finished yet

Also, the hyphen between "Cath" and "erine" is not displayed.

What am I doing wrong?

--Joel

\version "2.16.2"
\score {
  <<
    \relative c'' {
      c8 b a4 b c8 d |
    }
    \addlyrics {
      Cath _ -- erine wheel rolls _ |
    }
  >>
}