With ubuntu-mono-dark as icon-theme:
(gdb) r
Starting program: /home/xapantu/Dev/elementary/pantheon-files/build/src/pantheon-files 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffed7c3700 (LWP 18455)]
[New Thread 0x7fffe7fff700 (LWP 18456)]
[_LOG_LEVEL_INFO 22:15:26.243654] Welcome to Pantheon Files
[_LOG_LEVEL_INFO 22:15:26.243706] Version: 0.1
[_LOG_LEVEL_INFO 22:15:26.243842] Report any issues/bugs you might find to http://bugs.launchpad.net/pantheon-files
[New Thread 0x7fffe5709700 (LWP 18457)]
[New Thread 0x7fffe4f08700 (LWP 18458)]

Program received signal SIGSEGV, Segmentation fault.
gtk_icon_info_load_symbolic_for_context (icon_info=0x0, context=0x9a6630, was_symbolic=0x0, error=0x7fffffffd678) at /build/buildd/gtk+3.0-3.4.2/./gtk/gtkicontheme.c:3347
3347	/build/buildd/gtk+3.0-3.4.2/./gtk/gtkicontheme.c: Aucun fichier ou dossier de ce type.
(gdb) bt
#0  gtk_icon_info_load_symbolic_for_context (icon_info=0x0, context=0x9a6630, was_symbolic=0x0, error=0x7fffffffd678) at /build/buildd/gtk+3.0-3.4.2/./gtk/gtkicontheme.c:3347
#1  0x000000000047b8d1 in varka_icon_factory_load_symbolic_icon (self=<optimized out>, style=0x9a6630, iconname=<optimized out>, size=16) at /home/xapantu/Dev/elementary/pantheon-files/build/src/View/Chrome/IconFactory.c:150
#2  0x000000000047a7ff in marlin_view_chrome_view_switcher_construct (object_type=<optimized out>, action_group=<optimized out>) at /home/xapantu/Dev/elementary/pantheon-files/build/src/View/Chrome/ViewSwicher.c:282
#3  0x0000000000479e29 in marlin_view_chrome_top_menu_setup_items (self=0x99d000) at /home/xapantu/Dev/elementary/pantheon-files/build/src/View/Chrome/TopMenu.c:568
#4  0x000000000047a1af in marlin_view_chrome_top_menu_construct (object_type=<optimized out>, window=<optimized out>) at /home/xapantu/Dev/elementary/pantheon-files/build/src/View/Chrome/TopMenu.c:273
#5  0x0000000000467af5 in marlin_view_window_construct (object_type=<optimized out>, app=0x6be100, myscreen=<optimized out>) at /home/xapantu/Dev/elementary/pantheon-files/build/src/View/Window.c:1012
#6  0x000000000042f9d6 in open_window (application=0x6be100, location=0x83b500, screen=<optimized out>) at /home/xapantu/Dev/elementary/pantheon-files/src/marlin-application.c:77
#7  0x00000000004306de in open_windows (screen=0x71c080, n_files=0, files=0x0, application=0x6be100) at /home/xapantu/Dev/elementary/pantheon-files/src/marlin-application.c:93
#8  marlin_application_open_location (n_files=0, files=0x0, app=<optimized out>) at /home/xapantu/Dev/elementary/pantheon-files/src/marlin-application.c:397
#9  marlin_application_cmd (app=<optimized out>, cmd=<optimized out>) at /home/xapantu/Dev/elementary/pantheon-files/src/marlin-application.c:492
#10 0x00007ffff0c07a14 in ffi_call_unix64 () from /usr/lib/x86_64-linux-gnu/libffi.so.6
#11 0x00007ffff0c07435 in ffi_call () from /usr/lib/x86_64-linux-gnu/libffi.so.6
#12 0x00007ffff4f64b16 in g_cclosure_marshal_generic_va () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#13 0x00007ffff4f63eca in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#14 0x00007ffff4f7c741 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#15 0x00007ffff4f7d242 in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#16 0x00007ffff523adcc in g_application_run () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#17 0x000000000042868e in main (argc=1, argv=0x7fffffffe148) at /home/xapantu/Dev/elementary/pantheon-files/src/marlin-main.c:34
(gdb)