error CS0042: Unexpected error creating debug information file 'c:\UnrealEngine\Engine\Intermediate\Build\BuildRules\UE4Rules.PDB'

Output of the ue4-docker info command:

ue4-docker version:         0.0.81 (latest available version is 0.0.81)
Operating system:           Windows 10 Pro Version 2009 (OS Build 19041.867)
Docker daemon version:      20.10.5
NVIDIA Docker supported:    No
Maximum image size:         500GB
Available disk space:       732.21 GiB
Total system memory:        31.92 GiB physical, 36.67 GiB virtual
Number of processors:       8 physical, 8 logical

Additional details:

• Are you accessing the network through a proxy server? No

~I am actually running a modified version of ue4-docker (see #144) but I think this issue is not related to my changes.~ This is ruled out, stock ue4-docker 0.0.81 produces exactly the same behavior.

There is an independent report about the same issue with 4.25.3: https://github.com/adamrehn/ue4-docker/issues/99#issuecomment-716697043 by @Agendum.

Way to reproduce

1. Windows
2. ue4-docker build 4.26.1 --no-engine --exclude ddc --exclude templates --exclude debug
3. ue4-docker test 4.26.1

Expected

ue4-docker test passes

Actual

>ue4-docker test 4.26.1
[ue4-docker test] Starting a container using the "adamrehn/ue4-full:4.26.1" image...
[ue4-docker test] Running test "build-and-package.py"...
[RUN COMMAND] ['git', 'clone', '--depth=1', 'https://gitlab.com/ue4-test-projects/4.26/BasicCxx.git', 'C:\\Users\\ContainerAdministrator\\AppData\\Local\\Temp\\tmpo2dkttwc\\BasicCxx'] {}
Cloning into 'C:\Users\ContainerAdministrator\AppData\Local\Temp\tmpo2dkttwc\BasicCxx'...
[RUN COMMAND] ['ue4', 'package', 'Shipping'] {'cwd': 'C:\\Users\\ContainerAdministrator\\AppData\\Local\\Temp\\tmpo2dkttwc\\BasicCxx'}
Running AutomationTool...
Parsing command line: BuildCookRun -utf8output -clientconfig=Shipping -serverconfig=Shipping -project=C:\Users\ContainerAdministrator\AppData\Local\Temp\tmpo2dkttwc\BasicCxx\BasicCxx.uproject -noP4 -cook -build -stage -prereqs -pak -archive -platform=Win64 -nodebuginfo -allmaps -archivedirectory=C:\Users\ContainerAdministrator\AppData\Local\Temp\tmpo2dkttwc\BasicCxx\dist
Setting up ProjectParams for C:\Users\ContainerAdministrator\AppData\Local\Temp\tmpo2dkttwc\BasicCxx\BasicCxx.uproject
********** BUILD COMMAND STARTED **********
Running: C:\UnrealEngine\Engine\Binaries\DotNET\UnrealBuildTool.exe BasicCxxEditor Win64 Development -Project=C:\Users\ContainerAdministrator\AppData\Local\Temp\tmpo2dkttwc\BasicCxx\BasicCxx.uproject  C:\Users\ContainerAdministrator\AppData\Local\Temp\tmpo2dkttwc\BasicCxx\BasicCxx.uproject -NoUBTMakefiles  -Manifest=C:\Users\ContainerAdministrator\AppData\Local\Temp\tmpo2dkttwc\BasicCxx\Intermediate\Build\Manifest.xml -NoHotReload -log="C:\Users\ContainerAdministrator\AppData\Roaming\Unreal Engine\AutomationTool\Logs\C+UnrealEngine\UBT-BasicCxxEditor-Win64-Development.txt"
  Using 'git status' to determine working set for adaptive non-unity build (C:\Users\ContainerAdministrator\AppData\Local\temp\tmpo2dkttwc\BasicCxx).
  While compiling C:\UnrealEngine\Engine\Intermediate\Build\BuildRules\UE4Rules.dll:
  error CS0042: Unexpected error creating debug information file 'c:\UnrealEngine\Engine\Intermediate\Build\BuildRules\UE4Rules.PDB' -- 'Unspecified error '
  ERROR: Unable to compile source files.
Took 14.0685549s to run UnrealBuildTool.exe, ExitCode=6
UnrealBuildTool failed. See log for more details. (C:\Users\ContainerAdministrator\AppData\Roaming\Unreal Engine\AutomationTool\Logs\C+UnrealEngine\UBT-BasicCxxEditor-Win64-Development.txt)
AutomationTool exiting with ExitCode=6 (6)
BUILD FAILED
Using user-specified engine root: C:\UnrealEngine
Traceback (most recent call last):
  File "c:\python37\lib\runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "c:\python37\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Python37\Scripts\ue4.exe\__main__.py", line 9, in <module>
  File "c:\python37\lib\site-packages\ue4cli\cli.py", line 222, in main
    SUPPORTED_COMMANDS[command]['action'](manager, args)
  File "c:\python37\lib\site-packages\ue4cli\cli.py", line 94, in <lambda>
    'action': lambda m, args: m.packageDescriptor(os.getcwd(), args),
  File "c:\python37\lib\site-packages\ue4cli\UnrealManagerBase.py", line 454, in packageDescriptor
    self.packageProject(dir, args[0] if len(args) > 0 else 'Shipping', args[1:])
  File "c:\python37\lib\site-packages\ue4cli\UnrealManagerBase.py", line 429, in packageProject
    ] + extraArgs)
  File "c:\python37\lib\site-packages\ue4cli\UnrealManagerBase.py", line 371, in runUAT
    Utility.run([self.getRunUATScript()] + args, cwd=self.getEngineRoot(), raiseOnError=True)
  File "c:\python37\lib\site-packages\ue4cli\Utility.py", line 145, in run
    raise Exception('child process ' + str(command) + ' failed with exit code ' + str(returncode))
Exception: child process ['C:\\UnrealEngine\\Engine\\Build\\BatchFiles\\RunUAT.bat', 'BuildCookRun', '-utf8output', '-clientconfig=Shipping', '-serverconfig=Shipping', '-project=C:\\Users\\ContainerAdministrator\\AppData\\Local\\Temp\\tmpo2dkttwc\\BasicCxx\\BasicCxx.uproject', '-noP4', '-cook', '-build', '-stage', '-prereqs', '-pak', '-archive', '-platform=Win64', '-nodebuginfo', '-allmaps', '-archivedirectory=C:\\Users\\ContainerAdministrator\\AppData\\Local\\Temp\\tmpo2dkttwc\\BasicCxx\\dist'] failed with exit code 6
Using user-specified engine root: C:\UnrealEngine
Traceback (most recent call last):
  File "C:\workspace\build-and-package.py", line 22, in <module>
    run(['ue4', 'package', 'Shipping'], cwd=projectDir)
  File "C:\workspace\build-and-package.py", line 8, in run
    return subprocess.run(command, check=True, **kwargs)
  File "C:\Python37\lib\subprocess.py", line 512, in run
    output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command '['ue4', 'package', 'Shipping']' returned non-zero exit status 1.

I’m currently rerunning vanilla ue4-docker without my changes, but highly suspect that I will hit exactly the same error.

Additional thoughts

This might be caused by --exclude debug. Has anyone successfully passed ue4-docker test using an engine build with --exclude debug? Omiting --exclude debug is not an option for 4.26.1 because you’ll hit #99. If this assumption is true, it would mean that --exclude debug is unusable and needs fixes.

[slonopotamus]

So… I am observing exactly the same behavior using stock ue4-docker 0.0.81.

It means that my changes in #144 are actually unrelated.

It also means that ue4-docker cannot currently produce a working 4.26 engine on Windows. Or I don’t know a way how to achieve it.

[adamrehn]

I can’t remember which PDB files caused errors when they were removed (i.e. whether they were C++ or C# debug symbols), but I do know that when I attempted to build or package projects in a container image that didn’t have them, UnrealBuildTool complained about them being missing despite being listed in a manifest file somewhere.

In any case, the truncation hack was always fundamentally a workaround for the fact that I couldn’t figure out how PDB files are excluded from Installed Builds distributed through the Epic Games Launcher. If removing the PDB files listed in the Engine’s top-level .target files matches the results in a Launcher distribution then that would be my preferred approach, since the ideal goal is to produce results that match a Launcher build as closely as possible by default.