The function "FMaterialDerivativeAutogen::GetFunc1ReturnType(...)" does not have a case for "EFunc1::Exp2".
Also found in Release-5.4, CL: 331987674
1. Download the attached test project and open
2. Open the material "/Game/M_Crashy"
3. Connect the output of 'EXP2" node to "Base Color"
4. Observe the "check(0);"
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-208829 in the post.