Loading a CSV file with one line >=64k that will be stored in one cell leads to memory exhaustion. With online spelling activated immediately, else if the cell is placed into edit mode (F2). http://openoffice.org/bugzilla/show_bug.cgi?id=117400 has a test case attachment http://openoffice.org/bugzilla/attachment.cgi?id=76118
Fixed in master with http://cgit.freedesktop.org/libreoffice/libs-core/commit/?id=651568afad1a585c485384ab6d7b65780fb02256