It won't run in gdb...

Mon Apr 27 10:56:09 UTC 2020

: dub build
Performing "debug" build using 
/home/mark/opt/ldc2-1.21.0-linux-x86_64/bin/ldc2 for x86_64.
aaset 0.2.5: target for configuration "library" is up to date.
gtk-d:gtkd 3.9.0: target for configuration "library" is up to 
date.
debfind ~master: target for configuration "application" is up to 
date.
To force a rebuild of up-to-date targets, run again with --force.
: gdb DebFind
GNU gdb (Ubuntu 8.1-0ubuntu3.2) 8.1.0.20180409-git
[snip]
Reading symbols from DebFind...done.
(gdb) run
Starting program: /home/mark/app/d/debfind/DebFind
[Thread debugging using libthread_db enabled]
Using host libthread_db library 
"/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffeddfc700 (LWP 8186)]
[New Thread 0x7fffed5fb700 (LWP 8187)]
[New Thread 0x7fffe7fff700 (LWP 8188)]
[New Thread 0x7ffff7fe2700 (LWP 8189)]
[New Thread 0x7ffff7fdc700 (LWP 8190)]
[New Thread 0x7ffff7fd6700 (LWP 8191)]
[New Thread 0x7ffff7e64700 (LWP 8192)]
[New Thread 0x7ffff7e5e700 (LWP 8193)]
[New Thread 0x7ffff7e58700 (LWP 8194)]
[New Thread 0x7ffff7e52700 (LWP 8195)]

Thread 1 "DebFind" received signal SIGUSR1, User defined signal 1.
0x00007ffff50ba2ea in ?? () from 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
(gdb) bt
#0  0x00007ffff50ba2ea in  () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#1  0x00007ffff50bbae5 in  () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#2  0x00007ffff1af0e28 in  () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#3  0x00007ffff1af1bfc in  () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#4  0x00007ffff1aef823 in  () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#5  0x00007ffff1af050b in  () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#6  0x00007ffff1af40ed in XML_ParseBuffer () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#7  0x00007ffff50bab43 in  () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#8  0x00007ffff50baf76 in FcConfigParseAndLoad () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#9  0x00007ffff50bafe8 in FcConfigParseAndLoad () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#10 0x00007ffff50bb15e in  () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#11 0x00007ffff1af0e28 in  () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#12 0x00007ffff1af1bfc in  () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#13 0x00007ffff1aef823 in  () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#14 0x00007ffff1af050b in  () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#15 0x00007ffff1af40ed in XML_ParseBuffer () at 
/lib/x86_64-linux-gnu/libexpat.so.1
#16 0x00007ffff50bab43 in  () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#17 0x00007ffff50baf76 in FcConfigParseAndLoad () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#18 0x00007ffff50add24 in  () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#19 0x00007ffff50adf76 in  () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#20 0x00007ffff50a1a27 in  () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#21 0x00007ffff50a3ab5 in FcConfigSubstituteWithPat () at 
/usr/lib/x86_64-linux-gnu/libfontconfig.so.1
#22 0x00007ffff5cfe718 in  () at 
/usr/lib/x86_64-linux-gnu/libpangocairo-1.0.so.0
#23 0x00007ffff2c97552 in  () at 
/usr/lib/x86_64-linux-gnu/libpangoft2-1.0.so.0
#24 0x00007ffff5abfa67 in  () at 
/usr/lib/x86_64-linux-gnu/libpango-1.0.so.0
warning: (Internal error: pc 0x55555584c444 in read in psymtab, 
but not in symtab.)

warning: (Internal error: pc 0x55555584c430 in read in psymtab, 
but not in symtab.)

warning: (Internal error: pc 0x55555584c444 in read in psymtab, 
but not in symtab.)

#25 0x00007ffff5ac10c0 in pango_itemize_with_base_dir () at 
/usr/lib/x86_64-linux-gnu/libpango-1.0.so.0
warning: (Internal error: pc 0x55555584c444 in read in psymtab, 
but not in symtab.)

#26 0x00007ffff5ac974d in  () at 
/usr/lib/x86_64-linux-gnu/libpango-1.0.so.0
#27 0x00007ffff5acab32 in pango_layout_get_unknown_glyphs_count 
() at /usr/lib/x86_64-linux-gnu/libpango-1.0.so.0
#28 0x00007fffef522f8a in  () at 
/usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#29 0x00007fffef522ff8 in  () at 
/usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#30 0x00007fffef523168 in  () at 
/usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#31 0x00007ffff69bd9c5 in g_type_create_instance () at 
/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#32 0x00007ffff699e748 in  () at 
/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#33 0x00007ffff699fee5 in g_object_new_with_properties () at 
/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#34 0x00007ffff69a0961 in g_object_new () at 
/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#35 0x000055555584c445 in _D3gtk5EntryQg6__ctorMFZCQxQvQx 
(this=0x7ffff7f98800) at Entry.d:215
#36 0x0000555555749c80 in 
qtrac.debfind.appwindow.AppWindow.makeWidgets() 
(this=0x7ffff7ed7a00) at appwindow.d:85
#37 0x0000555555749919 in 
_D5qtrac7debfind9appwindow9AppWindow6__ctorMFC3gtk11ApplicationQnZCQCnQCkQCfQBy (this=0x7ffff7ed7a00, application=0x7ffff7ed0360) at appwindow.d:62
#38 0x0000555555784449 in 
_D5qtrac7debfind3app4mainFAAyaZ__T12__dgliteral2TC3gio11ApplicationQnZQBkMFQBaZv (GioApplication=0x7ffff7ed0360) at app.d:16
#39 0x000055555596d234 in 
_D7gobject8DClosureQj__T17d_closure_marshalTDFC3gio11ApplicationQnZvZQBtUPSQCv1c5types8GClosurePSQDrQwQw6GValuekQrPvQcZv (closure=0x555555cd52c0, return_value=0x0, n_param_values=1, param_values=0x7ffff7ef39a0, invocation_hint=0x7fffffffd6e0 "\b", marshal_data=0x0) at DClosure.d:122
#40 0x00007ffff699910d in g_closure_invoke () at 
/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#41 0x00007ffff69ac05e in  () at 
/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#42 0x00007ffff69b4715 in g_signal_emit_valist () at 
/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#43 0x00007ffff69b512f in g_signal_emit () at 
/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#44 0x00007ffff537ec55 in  () at 
/usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#45 0x00007ffff537ee66 in g_application_run () at 
/usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#46 0x000055555579a2e5 in _D3gio11ApplicationQn3runMFAAyaZi 
(this=0x7ffff7ed0360, argv=...) at Application.d:931
#47 0x0000555555784390 in D main (args=...) at app.d:18