Ok, I am making it crash every time in emacs 24.4.

Here's a stacktrace:

#0  0x00007fff91d43c7e in __kill () from
/usr/lib/system/libsystem_kernel.dylib
#1  0x00000001000b84f4 in terminate_due_to_signal (sig=6,
backtrace_limit=<optimized out>) at emacs.c:378
#2  0x00000001000d5863 in emacs_abort () at sysdep.c:2131
#3  0x00000001001a961c in ns_term_shutdown (sig=<optimized out>) at
nsterm.m:4451
#4  0x00000001000b86eb in shut_down_emacs (sig=32, stuff=<optimized out>)
at emacs.c:2050
#5  0x00000001000b84b9 in terminate_due_to_signal (sig=6,
backtrace_limit=40) at emacs.c:362
#6  0x00000001000d5863 in emacs_abort () at sysdep.c:2131
#7  0x00000001001b4d5d in ns_read_socket (terminal=0x1786d,
hold_quit=<optimized out>) at nsterm.m:3638
#8  0x00000001000bf3af in gobble_input () at keyboard.c:6850
#9  0x00000001000c5905 in handle_async_input () at keyboard.c:7090
#10 process_pending_signals () at keyboard.c:7104
#11 unblock_input_to (level=<optimized out>) at keyboard.c:7119
#12 unblock_input () at keyboard.c:7138
#13 0x00000001001b57ca in ns_set_vertical_scroll_bar (window=<optimized
out>, portion=<optimized out>, whole=<optimized out>,
    position=<optimized out>) at nsterm.m:3902
#14 0x000000010004cf50 in redisplay_window (window=<optimized out>,
just_this_one_p=<optimized out>) at xdisp.c:16912
#15 0x0000000100047fa9 in redisplay_window_1 (window=96365) at xdisp.c:14356
#16 0x0000000100138114 in internal_condition_case_1 (bfun=0x28, arg=32,
handlers=<optimized out>, hfun=<optimized out>) at eval.c:1372
#17 0x00000001000267e3 in redisplay_internal () at xdisp.c:14002
#18 0x0000000100027200 in redisplay_preserve_echo_area (from_where=96365)
at xdisp.c:14185
#19 0x000000010017a959 in wait_reading_process_output
(time_limit=<optimized out>, nsecs=<optimized out>, read_kbd=-1,
do_display=true,
    wait_for_cell=4320145466, wait_proc=0x0, just_wait_proc=<optimized
out>) at process.c:4704
#20 0x0000000100007d84 in sit_for (timeout=<optimized out>, reading=40,
display_option=<optimized out>) at dispnew.c:5861
#21 0x00000001000c0dfd in read_char (commandflag=1, map=4745847046,
prev_event=4320145466, used_mouse_menu=0x7fff5fbfc01f, end_time=0x0)
---Type <return> to continue, or q <return> to quit---
    at keyboard.c:2809
#22 0x00000001000bd833 in read_key_sequence (bufsize=30, keybuf=<optimized
out>, prompt=<optimized out>, dont_downcase_last=<optimized out>,
    can_return_switch_frame=<optimized out>, fix_current_buffer=<optimized
out>, prevent_redisplay=<optimized out>) at keyboard.c:9088
#23 0x00000001000bcec4 in command_loop_1 () at keyboard.c:1452
#24 0x0000000100137ffb in internal_condition_case (bfun=0x28,
handlers=<optimized out>, hfun=<optimized out>) at eval.c:1348
#25 0x00000001000cd22e in command_loop_2 (ignore=<optimized out>) at
keyboard.c:1177
#26 0x0000000100137993 in internal_catch (tag=<optimized out>, func=0x20,
arg=40) at eval.c:1112
#27 0x00000001000bb082 in command_loop () at keyboard.c:1148
#28 recursive_edit_1 () at keyboard.c:777
#29 0x00000001000ea27f in read_minibuf (map=<optimized out>,
initial=4320145466, prompt=<optimized out>, expflag=false,
    histvar=<optimized out>, histpos=<optimized out>, defalt=<optimized
out>, allow_props=<optimized out>, inherit_input_method=<optimized out>)
    at minibuf.c:674
#30 0x00000001000e9a7a in Fread_from_minibuffer (prompt=4722651153,
initial_contents=6, keymap=<optimized out>, read=40, hist=<optimized out>,
    default_value=4320145466, inherit_input_method=5) at minibuf.c:957
#31 0x000000010013999f in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2838
#32 0x0000000100171f6b in exec_byte_code (bytestr=<optimized out>,
vector=4347356341, maxdepth=<optimized out>, args_template=<optimized out>,
    nargs=<optimized out>, args=<optimized out>) at bytecode.c:916
#33 0x0000000100139699 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2861
#34 0x0000000100171f6b in exec_byte_code (bytestr=<optimized out>,
vector=4739000069, maxdepth=<optimized out>, args_template=<optimized out>,
    nargs=<optimized out>, args=<optimized out>) at bytecode.c:916
#35 0x0000000100139699 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2861
#36 0x0000000100135f04 in eval_sub (form=<optimized out>) at eval.c:2155
#37 0x0000000100137d7a in internal_lisp_condition_case (var=4347420722,
bodyform=4402638582, handlers=<optimized out>) at eval.c:1317
#38 0x0000000100172df5 in exec_byte_code (bytestr=<optimized out>,
vector=4738996165, maxdepth=<optimized out>, args_template=<optimized out>,
    nargs=<optimized out>, args=<optimized out>) at bytecode.c:1162
#39 0x0000000100139699 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2861
#40 0x0000000100135f04 in eval_sub (form=<optimized out>) at eval.c:2155
#41 0x0000000100137993 in internal_catch (tag=<optimized out>, func=0x20,
arg=40) at eval.c:1112
#42 0x0000000100172bb2 in exec_byte_code (bytestr=<optimized out>,
vector=4347335461, maxdepth=<optimized out>, args_template=<optimized out>,
    nargs=<optimized out>, args=<optimized out>) at bytecode.c:1097
#43 0x0000000100139699 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2861
#44 0x000000010013929d in Fapply (nargs=<optimized out>, args=<optimized
out>) at eval.c:2351
#45 0x0000000100139740 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2793
#46 0x0000000100171f6b in exec_byte_code (bytestr=<optimized out>,
vector=4347334021, maxdepth=<optimized out>, args_template=<optimized out>,
    nargs=<optimized out>, args=<optimized out>) at bytecode.c:916
#47 0x0000000100139699 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2861
#48 0x000000010013929d in Fapply (nargs=<optimized out>, args=<optimized
out>) at eval.c:2351
#49 0x0000000100139740 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2793
#50 0x0000000100171f6b in exec_byte_code (bytestr=<optimized out>,
vector=4347334021, maxdepth=<optimized out>, args_template=<optimized out>,
    nargs=<optimized out>, args=<optimized out>) at bytecode.c:916
#51 0x0000000100139699 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2861
#52 0x0000000100171f6b in exec_byte_code (bytestr=<optimized out>,
vector=4745497813, maxdepth=<optimized out>, args_template=<optimized out>,
    nargs=<optimized out>, args=<optimized out>) at bytecode.c:916
#53 0x000000010013a42f in funcall_lambda (fun=<optimized out>,
nargs=<optimized out>, arg_vector=<optimized out>) at eval.c:3045
#54 0x0000000100139699 in Ffuncall (nargs=<optimized out>, args=<optimized
out>) at eval.c:2861
#55 0x0000000100171f6b in exec_byte_code (bytestr=<optimized out>,
vector=4348836501, maxdepth=<optimized out>, args_template=<optimized out>,
    nargs=<optimized out>, args=<optimized out>) at bytecode.c:916
#56 0x0000000100138ff0 in apply_lambda (fun=4348836549, args=<optimized
out>, count=<optimized out>) at eval.c:2920


< ... more chopped out ... >

and I tried an xbacktrace:

"redisplay_internal (C function)" (0x53dbf0)
"read-from-minibuffer" (0x5fbfc568)
"helm-read-pattern-maybe" (0x5fbfc6a8)
0x1a776850 PVEC_COMPILED
"funcall" (0x5fbfc7d0)
0x1a775928 PVEC_COMPILED
"funcall" (0x5fbfcac0)
"helm-internal" (0x5fbfcd98)
"apply" (0x5fbfcec0)
"helm" (0x5fbfcff8)
"apply" (0x5fbfd120)
"helm" (0x5fbfd260)
"helm-projectile-find-file" (0x5fbfd428)
"projectile-switch-project-by-name" (0x5fbfd4c0)
"let" (0x5fbfd6c0)
0x1a825eb0 Lisp type 6
"apply" (0x5fbfd948)
"helm-funcall-with-source" (0x5fbfda80)
"helm-execute-selection-action-1" (0x5fbfdbb0)
"helm-execute-selection-action" (0x5fbfdcc0)
0x1a66a3b0 PVEC_COMPILED
"funcall" (0x5fbfddf0)
0x1a66a338 PVEC_COMPILED
"funcall" (0x5fbfe0e0)
"helm-internal" (0x5fbfe3b8)
"apply" (0x5fbfe4e0)
"helm" (0x5fbfe618)
"apply" (0x5fbfe740)
"helm" (0x5fbfe880)
"helm-projectile-switch-project" (0x5fbfea48)
0x534268 PVEC_SUBR
"ad-Advice-call-interactively" (0x5fbfed78)
"apply" (0x5fbfee78)
"call-interactively" (0x5fbfefc0)
"command-execute" (0x5fbff0e8)