make[2]: 正在进入目录 `/home/ncast/buildroot/output/build/gst-plugins-base-0.11.1/tools'
  CCLD   gst-discoverer-0.11
/home/ncast/buildroot/output/host/opt/ext-toolchain/bin/../lib/gcc/arm-none-linux-gnueabi/4.5.2/../../../../arm-none-linux-gnueabi/bin/ld: warning: libgstaudio-0.11.so.26, needed by ../gst-libs/gst/pbutils/.libs/libgstpbutils-0.11.so, not found (try using -rpath or -rpath-link)
../gst-libs/gst/pbutils/.libs/libgstpbutils-0.11.so: undefined reference to `gst_audio_format_get_info'
../gst-libs/gst/pbutils/.libs/libgstpbutils-0.11.so: undefined reference to `gst_audio_format_from_string'
collect2: ld returned 1 exit status

patch tools/Makefile.am and solve the problem

LDADD = $(top_builddir)/gst-libs/gst/pbutils/libgstpbutils-@GST_MAJORMINOR@.la\
        $(top_builddir)/gst-libs/gst/video/libgstvideo-@GST_MAJORMINOR@.la\
+       $(top_builddir)/gst-libs/gst/audio/libgstaudio-@GST_MAJORMINOR@.la\
+       $(top_builddir)/gst-libs/gst/interfaces/libgstinterfaces-@GST_MAJORMINOR@.la\
        $(GST_BASE_LIBS) $(GST_LIBS)
 
 AM_CFLAGS = $(GST_PLUGINS_BASE_CFLAGS) $(GST_BASE_CFLAGS) $(GST_CFLAGS)