I use Xephyr to play Sid Meier's Alpha Centauri (yes, people still play that),
and this requires disabling its Composite extension (or the game hangs).
Unfortunately, on my amd64 machine with Xephyr version 1.19.6 this throws an
error (used to work with version 1.19.5):

$ Xephyr :1 -screen 800x600 -extension Composite

Xephyr: ../../../../include/privates.h:122: dixGetPrivateAddr: Assertion `key-
(EE)
(EE) Backtrace:
(EE) 0: Xephyr (xorg_backtrace+0x4d) [0x5608257337bd]
(EE) 1: Xephyr (0x56082556d000+0x1ca559) [0x560825737559]
(EE) 2: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7f0b03af6000+0x12180)
[0x7f0b03b08180]
(EE) 3: /lib/x86_64-linux-gnu/libc.so.6 (gsignal+0x110) [0x7f0b037746a0]
(EE) 4: /lib/x86_64-linux-gnu/libc.so.6 (abort+0x1c7) [0x7f0b03775cf7]
(EE) 5: /lib/x86_64-linux-gnu/libc.so.6 (0x7f0b03740000+0x2cfca)
[0x7f0b0376cfca]
(EE) 6: /lib/x86_64-linux-gnu/libc.so.6 (0x7f0b03740000+0x2d042)
[0x7f0b0376d042]
(EE) 7: Xephyr (0x56082556d000+0x3c252) [0x5608255a9252]
(EE) 8: Xephyr (0x56082556d000+0x1c1c1f) [0x56082572ec1f]
(EE) 9: Xephyr (0x56082556d000+0x12c667) [0x560825699667]
(EE) 10: Xephyr (0x56082556d000+0x12bcc5) [0x560825698cc5]
(EE) 11: Xephyr (0x56082556d000+0x12b115) [0x560825698115]
(EE) 12: Xephyr (InitExtensions+0x3d) [0x56082562ce2d]
(EE) 13: Xephyr (0x56082556d000+0x7c93f) [0x5608255e993f]
(EE) 14: /lib/x86_64-linux-gnu/libc.so.6 (__libc_start_main+0xea)
[0x7f0b03760f2a]
(EE) 15: Xephyr (_start+0x2a) [0x5608255a92fa]
(EE)
(EE)
Fatal server error:
(EE) Caught signal 6 (Aborted). Server aborting
(EE)

Withour "-extension Composite" Xephyr starts, but unfortunately I can't play
the game. Given that this is the only reason I use Xephyr (and I suspect that
applies to many people as well), I think this bug qualifies as "important"...

Please report this upstream at
https://bugs.freedesktop.org/enter_bug.cgi?product=xorg&component=Server%2FDDX%2FXephyr
and let us know the bug number for tracking.

Thanks,
Andreas

Στις Παρασκευή, 16 Φεβρουαρίου 2018 12:40:41 Μ.Μ. EET γράψατε:


Thank you for you message. I've reported this bug upstream, it's bug # 105133
https://bugs.freedesktop.org/show_bug.cgi?id=105133