Changing the default value of a struct that is included as an array in another struct can prevent any Blueprints that use a DataTable made from the second struct from compiling. It appears to be a permanent issue that requires both involved structs, the DataTable, and the Blueprint to be deleted and re-created.
The compile fails with an error similar to "Error Invalid property 'CallFunc_GetDataTableRowFromName_OutRow' structure 'SecondStruct' error: Struct 'UserDefinedStruct /Game/SecondStruct.SecondStruct' Property 'TheStruct_6_94CBAF3C41107BBF392E338304F95177' Error ( Struct 'UserDefinedStruct /Engine/Transient.STRUCT_REINST_FirstStruct_3' is not compiled )". In addition, the variable names in the datatable have changed to now include apparent random hashes in the names.
The Blueprint compiles successfully.
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