Fermatas on last bar, snippet emits warnings

[Knute Snortum]

(LilyPond version 2.18.2)

This snippet:

http://lsr.di.unimi.it/LSR/Item?id=10

...work as advertized and produces two fermatas over the last bar line.  The only problem is what it emits these warnings:

document.ly:22:7: warning: Two simultaneous mark events, junking this one

\mark \markup { \musicglyph #"scripts.dfermata" }

document.ly:16:7: warning: Previous mark event here

\mark \markup { \musicglyph #"scripts.ufermata" }

I am working with the Mutopia Project, so my scripts cannot emit warnings.  Does anyone know why these warnings are printed?  Or, since the output is fine, can we stop the warnings?  (I know this violates the spirit of the "no warning" policy, but since we know it works...)

Knute Snortum

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