irssi segfault on /window theme handling

gistfile1.txt

vague@abigail:~$ gdb irssi core                                                                                                                                                                                                                                                                                                
GNU gdb (Ubuntu 7.7-0ubuntu3.1) 7.7
Copyright (C) 2014 Free Software Foundation, Inc.
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Reading symbols from irssi...done.
[New LWP 26711]
[New LWP 26713]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `irssi'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007fb6bb66f564 in g_hash_table_lookup () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
(gdb) backtrace
#0  0x00007fb6bb66f564 in g_hash_table_lookup () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x000000000044ff70 in theme_format_expand_abstract (flags=0, last_bg=0x7fffbe04b6a0, last_fg=0x7fffbe04b690, formatp=0x7fffbe04b708, theme=0x82a590) at themes.c:443
#2  theme_format_expand_data (theme=theme@entry=0x82a590, format=format@entry=0x7fffbe04b708, default_fg=..., default_bg=..., save_last_fg=save_last_fg@entry=0x0, save_last_bg=save_last_bg@entry=0x0, flags=flags@entry=16) at themes.c:548
#3  0x0000000000450bd7 in theme_format_expand (theme=theme@entry=0x82a590, format=0x7e470d "}", format@entry=0x7e4700 "{sb_window_bg}") at themes.c:634
#4  0x000000000042078c in statusbar_create (group=group@entry=0x862040, config=config@entry=0x2359e60, parent_window=parent_window@entry=0x83ad80) at statusbar.c:511
#5  0x00000000004209ba in statusbars_add_visible (window=0x83ad80) at statusbar.c:1047
#6  0x00007fb6bb69c6b8 in g_slist_foreach () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#7  0x0000000000489f22 in signal_emit_real (rec=rec@entry=0x8620b0, params=params@entry=1, va=va@entry=0x7fffbe04b878, first_hook=<optimized out>) at signals.c:242
#8  0x000000000048a38d in signal_emit (signal=signal@entry=0x499a3f "theme changed", params=params@entry=1) at signals.c:286
#9  0x0000000000451b4e in change_theme (verbose=0, name=<optimized out>) at themes.c:1339
#10 themes_reload () at themes.c:1393
#11 0x00007fb6b8fa92fd in XS_Irssi_abstracts_register (my_perl=<optimized out>, cv=<optimized out>) at Themes.xs:156
#12 0x00007fb6bbe1a866 in Perl_pp_entersub () from /usr/lib/libperl.so.5.18
#13 0x00007fb6bbe12e86 in Perl_runops_standard () from /usr/lib/libperl.so.5.18
#14 0x00007fb6bbda4490 in Perl_call_sv () from /usr/lib/libperl.so.5.18
#15 0x0000000000495940 in perl_call_signal (args=0x7fffbe04bc90, signal_id=<optimized out>, func=0xcb5d00, script=0xb97600) at perl-signals.c:301
#16 sig_func (p1=<optimized out>, p2=<optimized out>, p3=<optimized out>, p4=<optimized out>, p5=<optimized out>, p6=<optimized out>) at perl-signals.c:364
#17 0x0000000000489f22 in signal_emit_real (rec=rec@entry=0x7f61a0, params=params@entry=0, va=va@entry=0x7fffbe04bda8, first_hook=<optimized out>) at signals.c:242
#18 0x000000000048a38d in signal_emit (signal=signal@entry=0x49853e "setup changed", params=params@entry=0) at signals.c:286
#19 0x000000000048986a in settings_reread (fname=fname@entry=0x7db080 "/home/vague/.irssi/config") at settings.c:736
#20 0x0000000000445e21 in cmd_reload (data=<optimized out>) at fe-settings.c:307
#21 0x0000000000489f22 in signal_emit_real (rec=rec@entry=0x818770, params=params@entry=3, va=va@entry=0x7fffbe04bf38, first_hook=<optimized out>) at signals.c:242
#22 0x000000000048a38d in signal_emit (signal=signal@entry=0x2359b40 "command reload", params=params@entry=3) at signals.c:286
#23 0x0000000000476d43 in parse_command (item=0x22f8bf0, server=0x9401c0, expand_aliases=<optimized out>, command=0x235a5a1 "reload") at commands.c:899
#24 event_command (line=0x235a5a1 "reload", server=0x9401c0, item=0x22f8bf0) at commands.c:945
#25 0x0000000000489f22 in signal_emit_real (rec=rec@entry=0x7de790, params=params@entry=3, va=va@entry=0x7fffbe04c0e8, first_hook=<optimized out>) at signals.c:242
#26 0x000000000048a38d in signal_emit (signal=signal@entry=0x49868d "send command", params=params@entry=3) at signals.c:286
#27 0x000000000041a023 in key_send_line () at gui-readline.c:439
#28 0x0000000000489f22 in signal_emit_real (rec=rec@entry=0x858f60, params=params@entry=3, va=va@entry=0x7fffbe04c278, first_hook=<optimized out>) at signals.c:242
#29 0x000000000048a38d in signal_emit (signal=signal@entry=0x23595e0 "key send_line", params=params@entry=3) at signals.c:286
#30 0x000000000044c7f3 in sig_multi (data=<optimized out>, gui_data=0x0) at keyboard.c:639
#31 0x0000000000489f22 in signal_emit_real (rec=rec@entry=0x812000, params=params@entry=3, va=va@entry=0x7fffbe04c418, first_hook=<optimized out>) at signals.c:242
#32 0x000000000048a38d in signal_emit (signal=signal@entry=0x23b0610 "key multi", params=params@entry=3) at signals.c:286
#33 0x000000000044d143 in key_emit_signal (keyboard=0x83a3a0, key=0x84de30, key=0x84de30) at keyboard.c:538
#34 key_pressed (keyboard=0x83a3a0, key=key@entry=0x7fffbe04c540 "^J") at keyboard.c:594
#35 0x00000000004197d1 in sig_gui_key_pressed (keyp=0xa) at gui-readline.c:406
#36 0x0000000000489f22 in signal_emit_real (rec=rec@entry=0x85f250, params=params@entry=1, va=va@entry=0x7fffbe04c5f8, first_hook=<optimized out>) at signals.c:242
#37 0x000000000048a38d in signal_emit (signal=<optimized out>, params=1) at signals.c:286
#38 0x000000000041aa97 in sig_input () at gui-readline.c:664
#39 0x000000000047d800 in irssi_io_invoke (source=<optimized out>, condition=<optimized out>, data=<optimized out>) at misc.c:54
#40 0x00007fb6bb67fce5 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#41 0x00007fb6bb680048 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#42 0x00007fb6bb6800ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#43 0x0000000000416aac in main (argc=1, argv=0x7fffbe04c9a8) at irssi.c:356