using F12 alpha 1, using gdb to analyze cores leads to numerous assertion errors, eg:

(gdb) bt
../../gdb/objfiles.c:828: internal-error: qsort_cmp: Assertion `sect1_addr >= obj_section_endaddr (sect2)' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n) y

../../gdb/objfiles.c:828: internal-error: qsort_cmp: Assertion `sect1_addr >= obj_section_endaddr (sect2)' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Create a core file of GDB? (y or n) y
Aborted (core dumped)

gdb cannot print the bt regardless of if the session is aborted or not.

Before I installed all the necessary debuginfo files for the core (gnome-terminal) I was analyzing, I was able to get a bt (with some unresolved line numbers).