freeScreenInfo() is called from ddxGiveUp() during normal server
shutdown. If the server then aborts (e.g. due to the leak sanitizer
detecting leaks at exit), the signal handler calls AbortServer() which
calls ddxGiveUp() again, causing a double-free of pXWDHeader.
NULL out the pointer after freeing it to make the second call a no-op.
The X server accepts requests from client applications to create windows,
which are (normally rectangular) "virtual screens" that the client program
can draw into.
Windows are then composed on the actual screen by the X server
(or by a separate composite manager) as directed by the window manager,
which usually communicates with the user via graphical controls such as buttons
and draggable titlebars and borders.
As with other projects hosted on freedesktop.org, X.Org follows its
Code of Conduct, based on the Contributor Covenant. Please conduct
yourself in a respectful and civilized manner when using the above
mailing lists, bug trackers, etc:
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