ERROR in 'prompt.cc' at line 387: slot not a letter: _ (95)

Version: Dungeon Crawl Stone Soup 0.34-a0-2104-gda2984106b
Platform: unix
Bits: 64
Game mode: seeded
Tiles: online

Seed: 12213222783283602057, deterministic pregen: 1
Version history:
Game started: 0.34-a0-2102-g9c19a917d8
0.34-a0-2104-gda2984106b

Command line: /usr/games/crawl-git-da2984106b -name dossy -rc /dgldir/rcfiles/crawl-git/dossy.rc -macro /dgldir/rcfiles/crawl-git/dossy.macro -morgue /dgldir/morgue/dossy/ -seed -webtiles-socket /crawl-master/webserver/sockets/dossy:2026-01-27.02:23:54.sock -await-connection

RC options:
restart_after_game = false


Crash caused by signal #6: Aborted

Obtained 25 stack frames.
/usr/games/crawl-git-da2984106b(_Z17write_stack_traceP8_IO_FILE+0x3e) [0x58c72a2a839e]: write_stack_trace(_IO_FILE*)
/usr/games/crawl-git-da2984106b(_Z13do_crash_dumpv+0x43a) [0x58c72a2b65da]: do_crash_dump()
/usr/games/crawl-git-da2984106b(_Z20crash_signal_handleri+0x1fa) [0x58c72a2a887a]: crash_signal_handler(int)
/lib/x86_64-linux-gnu/libc.so.6(+0x42910) [0x717a95c42910]: 
/lib/x86_64-linux-gnu/libc.so.6(pthread_kill+0x11b) [0x717a95c9999b]: 
/lib/x86_64-linux-gnu/libc.so.6(raise+0x16) [0x717a95c42866]: 
/usr/games/crawl-git-da2984106b(+0x5019ad) [0x58c72a2b59ad]: 
/usr/games/crawl-git-da2984106b(_Z3diePKciS0_z+0x166) [0x58c72a2b6026]: die(char const*, int, char const*, ...)
/usr/games/crawl-git-da2984106b(_Z15letter_to_indexi+0x85) [0x58c72a7df115]: letter_to_index(int)
/usr/games/crawl-git-da2984106b(+0x79c501) [0x58c72a550501]: 
/usr/games/crawl-git-da2984106b(+0xcd4ad3) [0x58c72aa88ad3]: 
/usr/games/crawl-git-da2984106b(+0xcd4d22) [0x58c72aa88d22]: 
/usr/games/crawl-git-da2984106b(+0xce0833) [0x58c72aa94833]: 
/usr/games/crawl-git-da2984106b(+0xce3519) [0x58c72aa97519]: 
/usr/games/crawl-git-da2984106b(+0xcd4ded) [0x58c72aa88ded]: 
/usr/games/crawl-git-da2984106b(+0xcd3c33) [0x58c72aa87c33]: 
/usr/games/crawl-git-da2984106b(+0xcd5214) [0x58c72aa89214]: 
/usr/games/crawl-git-da2984106b(lua_pcallk+0x95) [0x58c72aa854c5]: 
/usr/games/crawl-git-da2984106b(_Z15debug_terp_dluaR4CLua+0xdf) [0x58c72a58767f]: debug_terp_dlua(CLua&)
/usr/games/crawl-git-da2984106b(+0xcbe532) [0x58c72aa72532]: 
/usr/games/crawl-git-da2984106b(+0xcbef75) [0x58c72aa72f75]: 
/usr/games/crawl-git-da2984106b(main+0x1f7) [0x58c72a1d9ef7]: 
/lib/x86_64-linux-gnu/libc.so.6(+0x280d0) [0x717a95c280d0]: 
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x89) [0x717a95c28189]: 
/usr/games/crawl-git-da2984106b(_start+0x25) [0x58c72a1da9e5]: 

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[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
0x0000717a95d0fbf7 in __GI___wait4 (pid=4187302, stat_loc=0x0, options=0, usage=0x0) at ../sysdeps/unix/sysv/linux/wait4.c:30
#0  0x0000717a95d0fbf7 in __GI___wait4 (pid=4187302, stat_loc=0x0, options=0, usage=0x0) at ../sysdeps/unix/sysv/linux/wait4.c:30
        sc_ret = -512
        sc_ret = <optimized out>
#1  0x000058c72a2a8a4c in call_gdb (file=0x717a95dff6c0 <_IO_2_1_stderr_>) at crash.cc:438
        gdb = <optimized out>
        attach_cmd = "attach 4186190\000\000\000\000\000"
#2  0x000058c72a2b65f8 in do_crash_dump () at dbg-asrt.cc:673
        t = 1769480640
        dir = "/dgldir/morgue/dossy/"
        name = "/dgldir/morgue/dossy/crash-dossy-20260127-022400.txt", '\000' <repeats 127 times>
        signal_info = "Crash caused by signal #6: Aborted"
        cause_msg = "ERROR in 'prompt.cc' at line 387: slot not a letter: _ (95)"
        file = 0x717a95dff6c0 <_IO_2_1_stderr_>
#3  0x000058c72a2a887a in crash_signal_handler (sig_num=6) at crash.cc:198
No locals.
#4  <signal handler called>
No locals.
#5  __pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:44
        tid = <optimized out>
        ret = 0
        pd = <optimized out>
        old_mask = {__val = {140721588127664}}
        ret = <optimized out>
        pd = <optimized out>
        old_mask = <optimized out>
        ret = <optimized out>
        tid = <optimized out>
        ret = <optimized out>
        resultvar = <optimized out>
        resultvar = <optimized out>
        __arg3 = <optimized out>
        __arg2 = <optimized out>
        __arg1 = <optimized out>
        _a3 = <optimized out>
        _a2 = <optimized out>
        _a1 = <optimized out>
        __futex = <optimized out>
        resultvar = <optimized out>
        __arg3 = <optimized out>
        __arg2 = <optimized out>
        __arg1 = <optimized out>
        _a3 = <optimized out>
        _a2 = <optimized out>
        _a1 = <optimized out>
        __futex = <optimized out>
        __private = <optimized out>
        __oldval = <optimized out>
#6  __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78
No locals.
#7  __GI___pthread_kill (threadid=<optimized out>, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
No locals.
#8  0x0000717a95c42866 in __GI_raise (sig=6) at ../sysdeps/posix/raise.c:26
        ret = <optimized out>
#9  0x000058c72a2b59ad in _BreakStrToDebugger (mesg=mesg@entry=0x7ffc4c45cfb0 "ERROR in 'prompt.cc' at line 387: slot not a letter: _ (95)", assert=false) at dbg-asrt.cc:807
No locals.
#10 0x000058c72a2b6026 in die (file=file@entry=0x58c72aad72ea "prompt.cc", line=line@entry=387, format=format@entry=0x58c72aad7315 "slot not a letter: %s (%d)") at dbg-asrt.cc:867
        tmp = "slot not a letter: _ (95)", '\000' <repeats 2022 times>
        mesg = "ERROR in 'prompt.cc' at line 387: slot not a letter: _ (95)", '\000' <repeats 2011 times>
        args = {{gp_offset = 40, fp_offset = 48, overflow_arg_area = 0x7ffc4c45d8b0, reg_save_area = 0x7ffc4c45d7d0}}
#11 0x000058c72a7df115 in letter_to_index (the_letter=95) at prompt.cc:387
No locals.
#12 0x000058c72a550501 in l_item_slot (item=<optimized out>, ls=