[Xwayland] segmentation fault

This happens when trying to run dosbox-SVN. Archlinux, Xwayland f08ab719, sway 1.5.1 and SDL1 1.2.x-hg.

(EE)
(EE) Backtrace:
(EE) 0: Xwayland (OsSigHandler+0x28) [0x58bff8]
(EE) 1: /usr/lib/libpthread.so.0 (funlockfile+0x60) [0x74caa02440f0]
(EE) 2: Xwayland (CheckPassiveGrabsOnWindow+0x9a) [0x56413a]
(EE) 3: Xwayland (ActivateEnterGrab+0xc7) [0x564cc7]
(EE) 4: Xwayland (CheckMotion+0x159) [0x564e69]
(EE) 5: Xwayland (WindowsRestructured+0x3a) [0x564f9a]
(EE) 6: Xwayland (UnmapWindow+0x136) [0x582b96]
(EE) 7: Xwayland (ProcUnmapWindow+0x4b) [0x552cbb]
(EE) 8: Xwayland (Dispatch+0x316) [0x558416]
(EE) 9: Xwayland (dix_main+0x364) [0x55c244]
(EE) 10: /usr/lib/libc.so.6 (__libc_start_main+0xf2) [0x74caa008f152]
(EE) 11: Xwayland (_start+0x2e) [0x43ae1e]
(EE)
(EE) Segmentation fault at address 0x0
(EE)
Fatal server error:
(EE) Caught signal 11 (Segmentation fault). Server aborting
(EE)

valgrind log xwayland.log

In Xwayland version 1.20.10, the mentioned application starts and works properly.