Solution : https://service.sap.com/sap/support/notes/791690 (SAP Service marketplace login required)
Key words : 
scheduling_failure/sapapo/saplbop_buffer reason, execute backorder processing, schedule line level, schedule line type, program termination occurs, program error, sales items, short dump, solution implement, prerequisites
Related Notes : 
       
| 375193 | Backorder processing: Composite SAP note on posting |