Signal 11; Project Editor Crashes 100% of the Time on Startup After Compiling Shaders

So, here’s the basic gist: I have used UE4.14 quite a bit, in the past, but I’m just now setting up my development rig, with a fresh install of Xubuntu 16.04. I haven’t reached the point of reimporting my old projects, because it’s not even loading new projects, yet.

  1. Editor fully loads, opens project browser/menu
  2. Can select various options for what the new project template should be, etc.
  3. Upon clicking the button to create the project, the editor successfully moves on to the next loading screen
  4. Loading screen reaches beyond 90%, possibly close to, if not at, 100%
  5. Editor has a complete crash, disappearing without displaying any errors

To see more of what’s going on, I have run the editor from the command line, using


Monitoring the terminal, I can see that it loads everything without complaint, with the exception that it seems to look for some Android images without success. The editor ignores these errors and moves on.

Other things I have tried:

  • Fresh install of UE
  • Using “No starter content” options
  • Using the blank project option, with no starter content
  • Deleting the “Saved” and “Intermediate” folders
  • Rebooting the system (from a cold boot), loading nothing but the UE editor and letting it load
  • Installing all drivers and making sure they are up to date
  • Waiting for the shaders to compile (at the project menu) 100% before starting any project
  • etc.

For that last one, if I wait at the menu for the shaders to compile, it crashes after finishing the compiling.

Also, now that I have waited for all of the shaders to compile, it crashes without loading even the project menu.



  • So, I tried the solution for changing the /Engine/ directory’s CHMOD. No good; not related to my problem.
  • Re-installed all video drivers, and carefully verified their functionality. Everything is working smoothly, just as before.
  • Tried deleting /DerivedDataCache/, waiting a half an hour for everything to recompile (35% and 45% marks), then it finally let me back into the project selection menu. I tried creating another project, again without starter content (just to be sure), and it seemed like it would just about load (shadowed box bordering an invisible window in the upper-left corner) but completely crashes.
  • Created a new project, scalable and with starter content, but still crashes.
  • Tried various new project settings (blueprint/C++, content/no content, maximum/scalable, etc.) without any noticeable difference.
  • Waited for the ~4k shaders to compile (at the project select menu), again. Once again, same error occurs, and now the editor will not startup without the same crash happening 100% of the time. It gets as far as being the Unreal Project Browser window with a light grey background filled in, then exits.

It almost feels like the solution is around the corner but it’s not working, yet.

Each time it crashes, the logs don’t seem to point to any error, nor can I seem to find a specific point in the logs in which everything goes from being okay to complete crash. It just goes through the procedures as normal, then says it’s quitting. Even when I start it from the console and monitor it closely for more verbose logs than what the files show, there still doesn’t appear to be any form of pinpointed error.

UPDATE: I have now pinpointed it down to being the signal 11 caught error.

Based upon other advice for the signal 11 error, and what I’ve read about it, in general, when relating to Linux itself, I have tried these things:

  • Verifying system integrity
  • Checking for hard drive errors
  • Checking RAM
  • Monitoring CPU temperature

All of the data says my system is okay, and that none of these things caused the signal 11 error.

This is now the area where the error seems to be catching pretty consistently:

[2018.01.21-10.28.18:667][  1]LogCollectionManager: Rebuilt the object cache for 0 collections in 0.000000 seconds (found 0 objects)
[2018.01.21-10.28.18:667][  1]LogCollectionManager: Fixed up redirectors for 0 collections in 0.000155 seconds (updated 0 objects)
[2018.01.21-10.28.22:327][  3]LogRenderer: Reallocating scene render targets to support 128x128 Format 10 NumSamples 1 (Frame:0).
Signal 11 caught.
Malloc Size=131076 LargeMemoryPoolOffset=131092 
CommonLinuxCrashHandler: Signal=11
Malloc Size=65535 LargeMemoryPoolOffset=196655 
Malloc Size=48134 LargeMemoryPoolOffset=244806 
LogPlatformFile: Not using cached read wrapper
LogInit: Display: RandInit(-975023168) SRandInit(-975023168).
LogTaskGraph: Started task graph with 4 named threads and 7 total threads with 1 sets of task threads.
LogInit: Build: ++UE4+Release-4.18-CL-0
LogInit: Engine Version: 4.18.3-0+++UE4+Release-4.18
LogInit: Compatible Engine Version: 4.18.0-0+++UE4+Release-4.18
LogInit: Net CL: 0
LogInit: Compiled (64-bit): Jan 21 2018 05:19:12
LogInit: Compiled with Clang: 3.8.0 (tags/RELEASE_380/final)
LogInit: Build Configuration: Shipping
LogInit: Branch Name: ++UE4+Release-4.18

Signal 11 is a segmentation fault, meaning the software tries to access memory it is not allowed to. So it´s quite probable this issue is not caused by some sort of general system integrity like CPU temperature but rather by a bug or incompability of the editor. From what I can get from the stack trace you provided it is checking for an intel GPU when it is crashing. So my recommendation would be to make a debug build of the editor and set a breakpoint in FDeferredShadingSceneRenderer::ShouldPrepareDistanceFieldScene() for further investigation.