cygwin x11 doesn't start after windows 10 upgrade

[Marco Atzeri]

On 11.06.2020 17:57, Steinar Bang wrote:
> Platform: amd64, windows 10 10.0.18363 Build 18363,
>            cygwin xorg-server 1.20.5-3, xlaunch 20160530-1
> 
> I start X11 by double clicking the following config.xlaunch:
>   https://gist.github.com/steinarb/8687e2113c601e061da909e75a180f39
> 
> After the reboot caused by a windows 10 upgrade, launching X11 using
> xlaunch have stopped working.
> 
> I have tried:
>   1. Running xlaunch directly instead of double clicking config.xlaunch
>   2. Running setup-86_64.exe to install all pending upgrades
>   3. Running setup-86_64.exe to reinstall xlaunch
>   4. Running setup-86_64.exe to reinstall xorg-server
> 
> But none of this has made any difference.
> 
> Does anyone have an idea what the problem might be?
> 
> Here's XWin.0.log from a startup attempt:
>   https://gist.github.com/steinarb/dacfec5172fd547cbec7c87723163193
> 
> Thanks1
> 
> 
> - Steinar
> 

Hi Steinar,
forgot to ask, there is stackdump  of Xwin ?

usually the stack dump are under /usr/bin

   ls /usr/bin | grep stack

but they can also be on your home directory
or in other places.

Re-looking at your Xwin.0.log
------------------------------------------------
XWin was started with the following command line:

XWin :0 -multiwindow -clipboard -wgl

ddxProcessArgument - Initializing default screens
winInitializeScreenDefaults - primary monitor w 1920 h 1080
winInitializeScreenDefaults - native DPI x 120 y 120
[ 24028.656] (II) xorg.conf is not supported
[ 24028.656] (II) See http://x.cygwin.com/docs/faq/cygwin-x-faq.html for 
more information
[ 24028.656] LoadPreferences: /cygdrive/d/Profiles/sbang/.XWinrc not found
[ 24028.656] LoadPreferences: Loading /etc/X11/system.XWinrc
[ 24028.656] LoadPreferences: Done parsing the configuration file...
[ 24028.671] winDetectSupportedEngines - RemoteSession: no
[ 24028.687] winDetectSupportedEngines - DirectDraw4 installed, allowing 
ShadowDDNL
[ 24028.687] winDetectSupportedEngines - Returning, supported engines 
00000005------------------------------------------------

on my log the next record is
    winSetEngine - Multi Window or Rootless => ShadowGDI

so it seems something is going wrong there

from "man Xwin" I see two possible options for troubleshooting
engine detection faults

-------------------------------------------------------
        -engine engine_type_id
                This option, which is intended for developers, overrides 
the  server's
                automatically  selected  drawing  engine type.  This 
parameter will be
                ignored if the specified drawing engine type is not 
supported  on  the
                current system.

                Default  behavior is to select the drawing engine with 
optimum perfor‐
                mance that supports the specified depth and window 
configuration.

                The engine type ids are:

                1   Shadow GDI

                4   Shadow DirectDraw Non-Locking
--------------------------------------------------------


on my system both options work, can you check on yours ?

    startxwin -- -engine 4