############################################
#  RUN PARAMETERS
############################################
auto_throttle=1
firstfit=1
bitcnt=3
bloom=1
bloom_bit_count=10
bloom_hash_count=24
bloom_oldest=1
cache=15
checkpoints=1
checksum=uncompressed
chunk_size=7
compaction=0
compression=zlib
data_extend=0
data_source=file
delete_pct=22
dictionary=0
evict_max=0
file_type=row-store
backups=0
huffman_key=0
huffman_value=0
insert_pct=13
internal_key_truncation=1
internal_page_max=9
isolation=read-committed
key_gap=14
key_max=256
key_min=256
leak_memory=0
leaf_page_max=9
logging=0
merge_max=4
merge_threads=3
mmap=1
ops=100000
prefix_compression=1
prefix_compression_min=3
repeat_data_pct=7
reverse=0
rows=100000
runs=100
split_pct=72
statistics=0
threads=13
value_max=2638
value_min=10
wiredtiger_config=
write_pct=36
############################################

T 12: main, sleeping
T 11: eviction server, the failing thread
T 10: sweep server, sleeping
T 3, 4, 5, 6, 7, 8, 9: worker threads, trying to do a named checkpoint and waiting  on format's hot-backup lock
T 2: doing a named checkpoint and trying to clear the tree's current eviction point
T 1: starting a transaction and doing a cache-full check, waiting to find a page on the eviction queue to evict.

WT-4  0x00000000004da528 in __wt_abort (session=0x803035280) at src/os_posix/os_abort.c:21
WT-5  0x0000000000459e3c in __wt_assert (session=0x803035280, error=0, file_name=0x531580 "src/btree/bt_discard.c", 
    line_number=56, fmt=0x522129 "%s") at src/support/err.c:452
WT-6  0x00000000004f5077 in __wt_page_out (session=0x803035280, pagep=0x807f293a0) at src/btree/bt_discard.c:56
WT-7  0x00000000004f4fff in __wt_ref_out (session=0x803035280, ref=0x807f293a0) at src/btree/bt_discard.c:32
WT-8  0x0000000000489898 in __rec_page_dirty_update (session=0x803035280, ref=0x807f293a0, exclusive=0)
    at src/btree/rec_evict.c:164
WT-9  0x0000000000488c0e in __wt_rec_evict (session=0x803035280, ref=0x807f293a0, exclusive=0) at src/btree/rec_evict.c:88
WT-10 0x0000000000473e6c in __wt_evict_page (session=0x803035280, ref=0x807f293a0) at src/btree/bt_evict.c:616
WT-11 0x0000000000474403 in __wt_evict_lru_page (session=0x803035280, is_app=0) at src/btree/bt_evict.c:1218
WT-12 0x0000000000474e12 in __evict_lru_pages (session=0x803035280, is_app=0) at src/btree/bt_evict.c:701
WT-13 0x0000000000475879 in __evict_lru (session=0x803035280, flags=3) at src/btree/bt_evict.c:794
WT-14 0x000000000047514c in __evict_pass (session=0x803035280) at src/btree/bt_evict.c:484
WT-15 0x000000000047352f in __evict_server (arg=0x803035280) at src/btree/bt_evict.c:162

and we're attempting to discard a dirty page:

52		/*
53		 * We should never discard a dirty page, the file's current eviction
54		 * point or a page queued for LRU eviction.
55		 */
56		WT_ASSERT(session, !__wt_page_is_modified(page));
57		WT_ASSERT(session, !F_ISSET_ATOMIC(page, WT_PAGE_EVICT_LRU));
58		WT_ASSERT(session, !F_ISSET_ATOMIC(page, WT_PAGE_SPLITTING));

and it's empty:

(gdb) p *page 
$4 = {u = {intl = {recno = 34466205048, parent_ref = 0x8065c10e8, __index = 0x0}, row = {d = 0x806588d78, ins = 0x8065c10e8, 
      upd = 0x0, entries = 0}, col_fix = {recno = 34466205048, bitf = 0x8065c10e8 "", entries = 0}, col_var = {
      recno = 34466205048, d = 0x8065c10e8, repeats = 0x0, nrepeats = 0, entries = 0}}, dsk = 0x0, modify = 0x806597520, 
  read_gen = 130743, memory_footprint = 3195, type = 7 '\a', flags_atomic = 0 '\0'}

(gdb) p *page->modify
$6 = {disk_snap_min = 0, rec_max_txn = 0, first_dirty_txn = 91156, update_txn = 91156, bytes_dirty = 3195, u1 = {replace = {
      addr = 0x0, size = 0 '\0', type = 2 '\002', reuse = 0 '\0'}, m = {multi = 0x0, multi_entries = 512}}, u2 = {intl = {
      root_split = 0x0, split_txn = 0}, leaf = {append = 0x0, update = 0x0}}, ovfl_track = 0x807704b00, write_gen = 1, 
  page_lock = 2 '\002', flags = 1 '\001'}

but there's one element on the page's insert list:

0x806588d30: row-store leaf
        disk 0x0, entries 0, dirty, empty, write generation=1
        insert {0000078100.00/opqrstuvwxyzabcdefghijklmnop ... }
        value {0000078100/LMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQR ... }

(gdb) skip_insert_single page->u.row.ins 0
... printing level 0
$12 = {upd = 0x8067e2800,
u = {recno = 1099511627800, key = {offset = 24, size = 256}}, next = 0x80670d990}
(gdb) p *$12.upd
$13 = {txnid = 91156, next = 0x0, size = 2407}