When cooking the DDC key for a material layers parameter set may become invalid which causes issues reading/writing to the global material shader map and can lead to a crash. See original UDN post for a detailed explanation.
Create a material using material layers feature.
Cook package.
Cook task may crash.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-64850 in the post.
| 0 |
| Component | UE - Graphics Features |
|---|---|
| Affects Versions | 4.19, 4.20, 4.21 |
| Target Fix | 4.22 |
| Fix Commit | 4734852 |
|---|
| Created | Oct 5, 2018 |
|---|---|
| Resolved | Jan 16, 2019 |
| Updated | Aug 9, 2019 |