This is an editor-only crash that's due to stack overflow/infinite recursion in UInheritableComponentHandler::FixComponentTemplateName(). We are recursively trying to rename other inherited component templates away from the new name to avoid a collision, but there is currently not a sufficient base case in place to break the recursion in this situation.

Note: This issue was first introduced in version 4.15 with the fix for [Link Removed].

Steps to Reproduce
  1. Launch the UE4 editor and create a new Actor-based blueprint class asset (Parent).
  2. In the blueprint editor, add 2 new StaticMesh components (name them 'MeshA' and 'MeshB') under the root.
  3. Compile, save and close the blueprint editor.
  4. Right-click on the 'Parent' asset and choose "Create Child Blueprint" (Parent_Child).
  5. Open it in the blueprint editor, select 'MeshA', change the 'StaticMesh' default value to /Engine/BasicShapes/Cube (or any valid mesh asset).
  6. Do the same for 'MeshB'. (Note: Steps 5 & 6 are required to ensure that we create/maintain component override records in the child class for these components. Otherwise, the issue will not occur.)
  7. Compile, save and close the blueprint editor.
  8. Close the editor, and then re-launch it.
  9. Double-click 'Parent' to open it in the blueprint editor, then swap the names on the components. (Note: It will be necessary to first rename 'MeshA' to something else so that you can rename 'MeshB' to 'MeshA'. Then you can change the temp name to 'MeshB'.)
  10. Compile, save and close the blueprint editor.
  11. Double-click 'Parent_Child' to attempt to open it. A crash will result:
    Exception thrown at 0x00007FF8182ABBCB (UE4Editor-Core-Win64-Debug.dll) in UE4Editor-Win64-Debug.exe: 0xC00000FD: Stack overflow (parameters: 0x0000000000000001, 0x0000003244203FE8).

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ComponentUE - Gameplay - Blueprint
Affects Versions4.
Target Fix4.22
Fix Commit4637103
CreatedOct 26, 2018
ResolvedDec 6, 2018
UpdatedFeb 23, 2021
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