Bug#1025419: libunwind 1.6.2-2 upgrade makes xorg crash on startup

[Thomas Glanzmann <thomas@glanzmann.de>]

Hello,
running Debian testing on apple silicon had the same issue. The culprit
seems to be that libunwind was recently updated to 1.6.2-2 which
triggers the issue for us. Downgrading to the old version works for us:

wget http://ftp.de.debian.org/debian/pool/main/libu/libunwind/libunwind8_1.3.2-2_arm64.deb
sudo dpkg -i libunwind8_1.3.2-2_arm64.deb

I also tried to build Xorg against the new libunwind, which did __not__
resolve the issue.

Output when libunwind is upgraded to 1.6.2-2:

(EE)
(EE) Backtrace:
(EE) 0: /usr/lib/xorg/Xorg (OsLookupColor+0x188) [0xaaaae58f96c8]
(EE) unw_get_proc_info failed: no unwind info found [-10]
(EE)
(EE) Segmentation fault at address 0x0
(EE)
Fatal server error:
(EE) Caught signal 11 (Segmentation fault). Server aborting
(EE)
(EE)
Please consult the The X.Org Foundation support
         at http://wiki.x.org
 for help.
(EE)

Cheers,
        Thomas