truncating a large table object fails

import wiredtiger, wttest

from helper import complex_populate, key_populate

# test_xxx.py

class test_xxx(wttest.WiredTigerTestCase):

    # Override WiredTigerTestCase, we have extensions.

    def setUpConnectionOpen(self, dir):

        conn = wiredtiger.wiredtiger_open(dir,

            'create,cache_size=100MB,' +

            'error_prefix="%s: "' % self.shortid())

        return conn

    def test_xxx(self):

        uri = 'table:xxx'

        config = 'allocation_size=512,' +\

            'leaf_page_max=512,value_format=S,key_format=S'

        nentries =  10000               # works

        nentries = 100000               # fails

        complex_populate(self, uri, config, nentries - 1)

        # Remove most of the object.

        c1 = self.session.open_cursor(uri, None)

        c1.set_key(key_populate(c1, 5))

        c2 = self.session.open_cursor(uri, None)

        c2.set_key(key_populate(c2, nentries - 5))

        self.session.truncate(None, c1, c2, None)

        c1.close()

        c2.close()

if __name__ == '__main__':

    wttest.run()

#0  __wt_err (session=0x805dbe420, error=22, 

    fmt=0x803730c22 "requires %s be set") at ../src/support/err.c:273

WT-1  0x00000008036e5f3e in __wt_cursor_kv_not_set (cursor=0x805cea200, key=1)

    at ../src/cursor/cur_std.c:71

WT-2  0x00000008036e05cd in __curfile_search (cursor=0x805cea200)

    at ../src/cursor/cur_file.c:175

WT-3  0x00000008036ee6cd in __wt_table_range_truncate (start=0x805cda680, 

    stop=0x805cda7c0) at ../src/cursor/cur_table.c:529

WT-4  0x00000008037195a0 in __wt_schema_range_truncate (session=0x805dbe420, 

    start=0x805cda680, stop=0x805cda7c0) at ../src/schema/schema_truncate.c:171

WT-5  0x000000080371c063 in __session_truncate (wt_session=0x805dbe420, uri=0x0, 

    start=0x805cda680, stop=0x805cda7c0, config=0x0)

    at ../src/session/session_api.c:546

Breakpoint 2, __wt_table_range_truncate (start=0x8015f8200, stop=0x8015f85c0)

    at ../src/cursor/cur_table.c:492

492             ctable = (start != NULL) ? start : stop;

(gdb) p *ctable

$12 = {iface = {session = 0x805d35410, uri = 0x801419520 "table:xxx",

    key_format = 0x8016bf10e "S", value_format = 0x8015451d0 "SiSS",

    get_key = 0x8036eade0 <__wt_curtable_get_key>,

    get_value = 0x8036eaf10 <__wt_curtable_get_value>,

    set_key = 0x8036eb3a0 <__wt_curtable_set_key>,

    set_value = 0x8036eb5d0 <__wt_curtable_set_value>,

    compare = 0x8036eb9d0 <__curtable_compare>,

    next = 0x8036ebe90 <__curtable_next>,

    prev = 0x8036ec200 <__curtable_prev>,

    reset = 0x8036ec380 <__curtable_reset>,

    search = 0x8036ec500 <__curtable_search>,

    search_near = 0x8036ec680 <__curtable_search_near>,

    insert = 0x8036ec850 <__curtable_insert>,

    update = 0x8036ecd00 <__curtable_update>,

    remove = 0x8036ed3b0 <__curtable_remove>,

    close = 0x8036ee200 <__curtable_close>, q = {tqe_next = 0x805cdd800,

      tqe_prev = 0x805cdd590}, recno = 0,

    raw_recno_buf = "\000\000\000\000\000\000\000\000", key = {data = 0x0,

      size = 0, flags = 0, mem = 0x0, memsize = 0}, value = {data = 0x0,

      size = 0, flags = 0, mem = 0x0, memsize = 0}, saved_err = 0,

    flags = 896}, table = 0x80141ad80,

  plan = 0x80153f7f0 "0vn3vr5vr1vn3vsr4vr2vn4vsr5vsrn", cfg = 0x8097ac8e0,

  cg_cursors = 0x80153feb0, idx_cursors = 0x0}

(gdb) xxx        <<<<<< xxx dumps column-group cursor flags & 0x60

$13 = 32

$14 = 64

$15 = 32

$16 = 32

$17 = 32

$18 = 32

(gdb) c

Continuing.

Breakpoint 2, __wt_table_range_truncate (start=0x8015f8200, stop=0x8015f85c0)

    at ../src/cursor/cur_table.c:492

492             ctable = (start != NULL) ? start : stop;

(gdb) xxx

$19 = 32

$20 = 64

$21 = 64

$22 = 0        <<<<<< cursor set-key flags are 0

$23 = 64

$24 = 64

(gdb) p ctable->cg_cursors[3].flags & 0x60

$26 = 0

(gdb) p *ctable->cg_cursors[3]

$28 = {session = 0x805d35410, uri = 0x8018a7ec0 "file:xxx_cgroup4.wt",

  key_format = 0x8016bf11c "S", value_format = 0x805ffb090 "Si",

  get_key = 0x8036e5630 <__wt_cursor_get_key>,

  get_value = 0x8036e9a50 <__wt_cursor_get_value>,

  set_key = 0x8036e5740 <__wt_cursor_set_key>,

  set_value = 0x8036e9e20 <__wt_cursor_set_value>,

  compare = 0x8036df230 <__curfile_compare>,

  next = 0x8036df5b0 <__curfile_next>, prev = 0x8036df850 <__curfile_prev>,

  reset = 0x8036df9a0 <__curfile_reset>,

  search = 0x8036dfad0 <__curfile_search>,

  search_near = 0x8036dfe30 <__curfile_search_near>,

  insert = 0x8036e01a0 <__curfile_insert>,

  update = 0x8036e07f0 <__curfile_update>,

  remove = 0x8036e0db0 <__curfile_remove>,

  close = 0x8036e1320 <__curfile_close>, q = {tqe_next = 0x805cde100,

    tqe_prev = 0x805cddb90}, recno = 0,

  raw_recno_buf = "\000\000\000\000\000\000\000\000", key = {

    data = 0x80df54988, size = 16, flags = 0, mem = 0x80bcc63e0,

    memsize = 16}, value = {data = 0x80d646fe9, size = 22, flags = 0,

    mem = 0x0, memsize = 0}, saved_err = 0, flags = 384}