Created attachment 6476
(Not very interesting) backtrace
This is possibly related to bug 11983; however, the crash is reproducible on current master (a1e737146f79aa2f4497984162ff20c8c7949fb5).
I ran git bisect on glib 2.44.0..2.46.0 and apparently the issue started with glib commit 779c809a3d07 (inotify: rewrite inotify-kernel). 
I've noticed the crash occurring in two possible places in thunar-file.c:thunar_file_compare_by_name():
4023 /* case insensitive checking */
4024 if (G_LIKELY (!case_sensitive))
4025 result = strcmp (file_a->collate_key_nocase, file_b->collate_key_nocase);
4027 /* fall-back to case sensitive */
4028 if (result == 0)
4029 result = strcmp (file_a->collate_key, file_b->collate_key);
I've had instances of crashes at either strcmp() and, weirdly enough, sometimes none of the arguments are null and other times one or both are null. During one debugging session, I was able to jump to frame #1 in GDB and do:
(gdb) call strcmp (file_a->collate_key_nocase, file_b->collate_key_nocase)
and the function call didn't result in a segmentation fault, even though GDB had previously reported that it did.
All in all, I'm not sure what's going here. I suppose it could be a bug in glib but I failed to produce a crash in nautilus while repeatedly renaming the same file.
Can you describe how you made Thunar crash while using gdb? I can reproduce the bug only outside of any debugging environment (gdb, valgrind).
(In reply to flo.xfce from comment #1)
> Can you describe how you made Thunar crash while using gdb? I can reproduce
> the bug only outside of any debugging environment (gdb, valgrind).
I am not doing anything special when running it under GDB; I only make sure to kill any Thunar daemons before starting gdb (`killall Thunder; gdb thunar`).
(In reply to Evangelos Foutras from comment #2)
> `killall Thunder; gdb thunar`
I meant "killall Thunar" here.
one important details to reproduce, you need to use the clipboard. let's say you have to files file_1 and file_2. in order to reproduce, select file_1 and press F2, delete file_1, then select file_2 and paste the copied name (file_1) press enter BOOM
Likely a duplicate.
*** This bug has been marked as a duplicate of bug 12264 ***