undefined reference to interface

[Joël Krähemann <weedlight gmail com>]

hi, me just did a new Makefile.am and organizing code into libraries.

now me get a lot of following messages especially related to interfaces:

...
/home/minos/ags-code/src/ags/audio/recall/ags_volume_recycling.c:101:
undefined reference to `ags_dynamic_connectable_get_type'
libags_audio.a(libags_audio_a-ags_buffer_audio_signal.o): In function
`ags_buffer_audio_signal_get_type':
/home/minos/ags-code/src/ags/audio/recall/ags_buffer_audio_signal.c:110:
undefined reference to `ags_dynamic_connectable_get_type'
libags_audio.a(libags_audio_a-ags_copy_audio_signal.o): In function
`ags_copy_audio_signal_get_type':
/home/minos/ags-code/src/ags/audio/recall/ags_copy_audio_signal.c:112:
undefined reference to `ags_dynamic_connectable_get_type'
libags_audio.a(libags_audio_a-ags_volume_audio_signal.o): In function
`ags_volume_audio_signal_get_type':
/home/minos/ags-code/src/ags/audio/recall/ags_volume_audio_signal.c:114:
undefined reference to `ags_dynamic_connectable_get_type'

The interface was compiled but somehow linker can't find appropriate
interface's get_type

Visit my project on: http://ags.sf.net

bests
Joël