Hello everyone,

Just to keep you up to date, I switched tack and have been using the
"GALLIUM_DDEBUG" environment variable to try and capture data about the crash.
I found out about this option via a Google search. As I understand it, it
creates fences around each GPU operation to detect when and if they complete,
dumping the contents of the draw call if it doesn't finish in a timely way.

Unfortunately, I haven't been able to reproduce the crash with this variable
enabled, despite playing for more than 5 hours (not consecutively.) The
GALLIUM_DDEBUG mode is certainly working as performance is quite severely
impacted. Maybe the way GALLIUM_DDEBUG is implemented unfortunately also
prevents the issue from happening.

All I can say so far is that I suspect the problem is related to vertex buffer
drawing. On one occasion I disabled the fences around vertex buffer drawing
while enabling GALLIUM_DDEBUG (to try and get some more performance) and I did
experience a hard lock as usual. I will continue running in this mode to see if
it turns up a result.

If anyone else would like to try, you can modify the
"~/.steam/steamapps/common/XCom-Enemy-Unknown/binaries/linux/xcom.sh" file. On
a line before the call to "${GAMEBINARY}", write "export GALLIUM_DDEBUG=800".
You can probably also set this environment variable before running Steam.

Thank you Paulo for your suggestion, I will try that if I have time to see if
it affects the frequency of the crashes.

The commit I tested with was 55365a7ad50c2e4547f58995a8e3411d8f2b00a2