What does the second column in the gdb stack trace mean?

I have a stack trace that looks like this:

#3  0x00007fffde86c206 in GetMedia (p_ml=0xb91560, id=<value optimized out>, select=ML_MEDIA, reload=<value optimized out>) at ../../../modules/media_library/sql_media_library.c:1170
#4  0x00007fffde86a7d0 in GetInputItemFromMedia (p_ml=0xb91560, i_media=12276000) at ../../../modules/media_library/sql_media_library.c:1204
#5  0x00007ffff6765eab in ml_CreateInputItem (this=0x7784f0) at ../../../../include/vlc_media_library.h:887
#6  MLModel::popupInfo (this=0x7784f0) at ../../../../modules/gui/qt4/components/playlist/media_library/ml_model.cpp:528
#7  0x00007ffff67a7204 in MLModel::qt_metacall (this=0x7784f0, _c=<value optimized out>, _id=17710, _a=<value optimized out>) at components/playlist/media_library/ml_model.moc.cpp:79
#8  0x00007ffff4ec8e3f in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib/libQtCore.so.4

I'm wondering that the second column signifies. Also, what does the lack of it signify? As can be seen, frame 开发者_如何学编程#6 does not have this address, and I believe my problem( a segfault ) is being caused due to something related.

That column contains the return address from the called function just above to the caller function on that line. Its lack probably means that the function was inlined.