[5.8] Chunking / Pak File Generation Bug for MacOS

General Issues and Bug Reporting (Unreal Engine)
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Summary

This Post is two Errors that I believe are connected, they both revolve around chunking.

Issue One:
This Is for Asset Audit. When clicking Add Chunks you will either see an error message and a call stack message log if running in editor or you will hit a break point if using IDE. Also occasionally you will see a Mac popup for crash of app but it disappears fast and the app does not fully crash.
EDIT: Add Chunks shows error message for Windows as well but when switching Selected Platform to Windows you still see all the chunks unlike Mac where you will only see chunk0

Issue Two:
When Packaging Project for any config on Mac it will always only generate pakchunk0. But if you were to do the same thing on windows you will get the expected result of multiple paks.

What Type of Bug are you experiencing?

Editor

Steps to Reproduce

Pre Requirements

  1. Got to ProjectSetting>Packaging
  2. Check Generate Chunks
  3. Uncheck Use IO Store (Unsure if you will still run into the same issue if checked as I have not tested it)
  4. Ensure Use Pak File is Checked
  5. Create at least two PAL In Different Locations

Settings For PAL’s (Feel Free to change them as I doubt they matter much for the result)
Apply Recursively: False
Cook Rule: Always Cook
Label Assets In My Directory: True
Is Runtime Label: True
Include Redirectors: True
Rest Default

Issue One Steps:

  1. Open Asset Audit
  2. Click Add Chunks

Issue Two Steps:

  1. Package Project for any config
  2. Once packaged go to folder containing AppName.app
  3. Right Click on AppName.app and click on “Show Package Contents”
  4. Navigate to Contents/UE/Content/Paks/ and you will see on pakchunk0

Expected Result

Issue One Expected Result:
Chunks Show In Audit Without opening a message log with a callstack/Hitting Breakpoint if running from IDE

Issue Two Expected Result:
The Right Amount Of Paks Are Generated. IE: if there are two PAL’s with ID 1, 2 then we should see: pakchunk0, packchunk1, packchunk2

Observed Result

Issue One Result:

  1. A huge call stack error message log appears
  2. Chunks then appear
  3. sometimes Mac crash windows shows up really fast

Issue two Result:
the default pak aka. pakchunk0 is the only one ever generated for all configs

Affects Versions

5.8

Platform(s)

Mac

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For crash reports, include your callstack

Full Message Log Message From Issue One:

Ensure condition failed: false  [File:./Runtime/CoreUObject/Private/UObject/TopLevelAssetPath.cpp] [Line: 132] 
Short asset name used to create FTopLevelAssetPath: "PackageChunk.PackageChunk"
Stack: 
0x03ab719c libUnrealEditor-CoreUObject.dylib!FTopLevelAssetPath::TrySetPath(TStringView<char16_t>)::$_0::operator()() const   [UnknownFile]) 
0x03aba274 libUnrealEditor-CoreUObject.dylib!FTopLevelAssetPath::TrySetPath(TStringView<char16_t>) (.cold.2)   [UnknownFile]) 
0x038957a0 libUnrealEditor-CoreUObject.dylib!FTopLevelAssetPath::TrySetPath(TStringView<char16_t>)   [UnknownFile]) 
0x29f58220 libUnrealEditor-ContentBrowser.dylib!SAssetView::SetMajorityAssetType(FName)   [UnknownFile]) 
0x29f56014 libUnrealEditor-ContentBrowser.dylib!SAssetView::Tick(FGeometry const&, double, float)   [UnknownFile]) 
0x087c0a24 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087bfeec libUnrealEditor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c03f4 libUnrealEditor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c03f4 libUnrealEditor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x07d0f928 libUnrealEditor-Slate.dylib!SBorder::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087bfeec libUnrealEditor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c03f4 libUnrealEditor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c03f4 libUnrealEditor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x07d0f928 libUnrealEditor-Slate.dylib!SBorder::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c53a0 libUnrealEditor-SlateCore.dylib!SOverlay::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087bfeec libUnrealEditor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c03f4 libUnrealEditor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c5e2c libUnrealEditor-SlateCore.dylib!SPanel::PaintArrangedChildren(FPaintArgs const&, FArrangedChildren const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x07d99ff4 libUnrealEditor-Slate.dylib!SSplitter::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c53a0 libUnrealEditor-SlateCore.dylib!SOverlay::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087bfeec libUnrealEditor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c53a0 libUnrealEditor-SlateCore.dylib!SOverlay::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c03f4 libUnrealEditor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087bfeec libUnrealEditor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087bfeec libUnrealEditor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c53a0 libUnrealEditor-SlateCore.dylib!SOverlay::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c03f4 libUnrealEditor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087c1380 libUnrealEditor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const   [UnknownFile]) 
0x087d9764 libUnrealEditor-SlateCore.dylib!SWindow::PaintSlowPath(FSlateInvalidationContext const&)   [UnknownFile]) 
0x085b6d7c libUnrealEditor-SlateCore.dylib!FSlateInvalidationRoot::PaintInvalidationRoot(FSlateInvalidationContext const&)   [UnknownFile]) 
0x087d9ad0 libUnrealEditor-SlateCore.dylib!SWindow::PaintWindow(double, float, FSlateWindowElementList&, FWidgetStyle const&, bool)   [UnknownFile]) 
0x07a4a9d8 libUnrealEditor-Slate.dylib!FSlateApplication::DrawWindowAndChildren(TSharedRef<SWindow, (ESPMode)1> const&, FDrawWindowArgs&)   [UnknownFile]) 
0x07a4ad68 libUnrealEditor-Slate.dylib!FSlateApplication::DrawWindowAndChildren(TSharedRef<SWindow, (ESPMode)1> const&, FDrawWindowArgs&)   [UnknownFile]) 
0x07a4a350 libUnrealEditor-Slate.dylib!FSlateApplication::PrivateDrawWindows(TSharedPtr<SWindow, (ESPMode)1>)   [UnknownFile]) 
0x07a49bc4 libUnrealEditor-Slate.dylib!FSlateApplication::DrawWindows()   [UnknownFile]) 
0x07a4d9ac libUnrealEditor-Slate.dylib!FSlateApplication::TickAndDrawWidgets(float)   [UnknownFile]) 
0x07a4cf04 libUnrealEditor-Slate.dylib!FSlateApplication::Tick(ESlateTickType)   [UnknownFile]) 
0x00c8d8c8 UnrealEditor!FEngineLoop::Tick()   [UnknownFile]) 
0x00c91488 UnrealEditor!GuardedMain(char16_t const*)   [UnknownFile]) 
0x00ca8afc UnrealEditor!-[UEAppDelegate runGameThread:]   [UnknownFile]) 
0x04f55ad8 libUnrealEditor-Core.dylib!-[FCocoaGameThread main]   [UnknownFile]) 
0x8c546a90 Foundation!__NSThread__start__()   [UnknownFile]) 
0x8ac47c58 libsystem_pthread.dylib!_pthread_start()   [UnknownFile]) 
0x8ac42c1c libsystem_pthread.dylib!thread_start()   [UnknownFile])

Additional Notes

This Was Tested On Both A brand New Project Created On 5.8 on Mac and A Project Migrated from 5.7.4 Being developed on multiple platforms where the others do generate pak files.

If you require any clarification or anything else feel free to reach out.