If you enable Shader compilation via XGE by setting r.XGEShaderCompile = 1 in ConsoleVariables.ini in 4.18 Editor downloaded from Launcher, it prevents shaders from compiling at all, and as a result sometimes the editor will never finish loading because it's waiting on shaders to compile. Additionally, launch on/cooking/packaging is not possible.

Licensee reports this happens when they make a build with InstalledBuild.xml themselves as well.

This issue does NOT reproduce in Release-4.18, only in a build created with BuildGraph and InstalledBuild.xml (so it does reproduce in 4.18 downloaded from the Epic Games Launcher)

From Luke Thatcher: “This might break if the InstalledBuild script does not include XGEControlWorker.exe in the launcher build. This was a new .exe (actually just an on-disk copy of ShaderCompileWorker.exe), which is required for the new XGE interception system to function.”

Steps to Reproduce
  1. Uncomment this line in Engine/Config/ConsoleVariables.ini (remove semicolon at beginning):
    ; Uncomment to enable XGE shader compilation.
    ;r.XGEShaderCompile = 1
  2. Create a new project and hit Ctrl+Shift+. to recompile shaders, or create a new simple material or change an existing one and try to recompile.

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Fix Commit3856169
Main Commit3990065
Release Commit3856169
CreatedNov 9, 2017
ResolvedJan 25, 2018
UpdatedApr 27, 2018
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