Trying to sync my several years old wallet using bitcoin-qt on Linux WITH PRUNING ON. After 44% (around Dec. 3 2017, 16:xx), it quits with a segmentation fault. Guessing from the date, I could have made a transaction from that wallet around that time. Tried different computers with different flavors of Linux (Ubuntu 20.04, q4os 20.04) to no avail. If I am syncing without a wallet, it works.
Here, logs from a run with GDB and a subsequent backtrace (not sure if that helps, please contact me for debug info):

Reading symbols from ./bitcoin/bitcoin-0.21.0/bin/bitcoin-qt...
(No debugging symbols found in ./bitcoin/bitcoin-0.21.0/bin/bitcoin-qt)
(gdb) start
Function "main" not defined.
Make breakpoint pending on future shared library load? (y or [n]) n
Starting program: /home/chrischan/bitcoin/bitcoin-0.21.0/bin/bitcoin-qt
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff742f700 (LWP 32345)]
[New Thread 0x7ffff63dc700 (LWP 32346)]
[New Thread 0x7ffff5a9a700 (LWP 32347)]
[New Thread 0x7fffe6ffe700 (LWP 32348)]
[New Thread 0x7fffe67fd700 (LWP 32349)]
[New Thread 0x7fffc5881700 (LWP 32350)]
[New Thread 0x7fff4a870700 (LWP 32353)]
[New Thread 0x7fff42ee6700 (LWP 32354)]
[Thread 0x7fff4a870700 (LWP 32353) exited]
[New Thread 0x7fff426e5700 (LWP 32355)]
[New Thread 0x7fff41ee4700 (LWP 32356)]
[New Thread 0x7fff416e3700 (LWP 32357)]
[New Thread 0x7fff40ee2700 (LWP 32358)]
[New Thread 0x7fff2bfff700 (LWP 32359)]
[New Thread 0x7fff2b7fe700 (LWP 32360)]
[New Thread 0x7fff2affd700 (LWP 32361)]
[New Thread 0x7fff2a7fc700 (LWP 32362)]
[Thread 0x7fff41ee4700 (LWP 32356) exited]

Thread 6 "b-scheduler" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffe67fd700 (LWP 32349)]
0x0000555555c2ba7b in ?? ()
(gdb) bt
#0 0x0000555555c2ba7b in ?? ()
#1 0x0000555555c4d72d in ?? ()
#2 0x0000555555c4e03d in ?? ()
#3 0x0000555555c4e454 in ?? ()
#4 0x0000555555ac964b in ?? ()
#5 0x0000555555da43b0 in ?? ()
#6 0x0000555555da31ca in ?? ()
#7 0x00005555558a097b in ?? ()
#8 0x0000555555e6e58a in ?? ()
#9 0x00007ffff7f9c609 in start_thread (arg=) at pthread_create.c:477
#10 0x00007ffff7c16293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
(gdb)

System information

V21.0, from website, verified signature

(1) Old asus EeePc, 2MB RAM, 250GB SSD
(2) Acer Laptop, 4MB RAM, 250GB SSD

Ubuntu 20.04
Q4OS (latest)