[mythtv] Link failure with clang

[Craig Treleaven]

Hi:

I'm not a developer so I'm probably missing something obvious.  I'm 
trying to build mythtv-fixes 0.26 on OS X using clang for MacPorts. 
It fails with the following error message:

>Undefined symbols for architecture x86_64:
>   "_dvdnav_get_highlight_area_from_group", referenced from:
>       DVDRingBuffer::DVDButtonUpdate(bool) in dvdringbuffer.o

This arose following a commit on January 20, 2013:

https://github.com/MythTV/mythtv/commit/012ebe9de7e20a0bae1920cfc55199ad63937636

I can build versions of 0.26 prior to this commit.

Going further out onto a shaky branch, I think otool is telling me 
that the problem symbol _is_ in the referenced file:

>  > otool -rv 
>/opt/local/var/macports/build/_Users_mytthtv_macports_mythtv-core.26_2/mythtv-core.26/work/mythtv-65e6136a7/mythtv/libs/libmythtv/dvdringbuffer.o 
>|grep highlight
>0000bb5d True  long   True   BRANCH  False     _dvdnav_get_current_highlight
>0000a02f True  long   True   BRANCH  False 
>_dvdnav_get_highlight_area_from_group
>0000a009 True  long   True   BRANCH  False     _dvdnav_get_current_highlight

I'm happy to provide more information; I just don't know what else 
might be relevant.

Could someone knowledgeable help me understand why this isn't working?

Thanks,

Craig