I tried it here. I don't get a crash; I get a rather long delay and
then
psql:vlad.sql:61: NOTICE: Error occurred while executing PL/pgSQL function sp_loc_parent_check
psql:vlad.sql:61: NOTICE: line 12 at return
psql:vlad.sql:61: ERROR: Memory exhausted in AllocSetContextCreate(8192)
which is not too surprising seeing that your function is in an infinite
recursion (chasing the loop 96 -> 15 -> 3 -> 96 that your insert has
created).
It would be interesting to know why your copy SEGV's rather than
recovering gracefully. Can you provide a debugger backtrace from the
coredump?
regards, tom lane