Backtrace:
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/reconcile/rec_write.c:4260(__rec_row_merge)[0x457c46]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/reconcile/rec_write.c:4146(__rec_row_int)[0x4576dc]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/reconcile/rec_write.c:409(__wt_reconcile)[0x44fe9d]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/btree/bt_sync.c:165(__sync_file)[0x49ed19]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/btree/bt_sync.c:256(__wt_cache_op)[0x49ef59]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/txn/txn_ckpt.c:981(__checkpoint_worker)[0x47863d]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/txn/txn_ckpt.c:1063(__wt_checkpoint)[0x478952]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/txn/txn_ckpt.c:184(__checkpoint_apply)[0x4762f4]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/txn/txn_ckpt.c:464(__wt_txn_checkpoint)[0x47736b]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/../src/session/session_api.c:912(__session_checkpoint)[0x469dee]
/home/jenkins/jenkins/workspace/wiredtiger-test-format-stress/build_posix/test/format/../../../test/format/ops.c:351(ops)[0x40f691]

############################################
#  RUN PARAMETERS
############################################
abort=0
auto_throttle=1
firstfit=0
bitcnt=1
bloom=1
bloom_bit_count=14
bloom_hash_count=15
bloom_oldest=0
cache=63
checkpoints=1
checksum=off
chunk_size=4
compaction=0
compression=lz4
data_extend=0
data_source=table
delete_pct=20
dictionary=0
evict_max=0
file_type=row-store
backups=0
huffman_key=0
huffman_value=0
insert_pct=20
internal_key_truncation=1
internal_page_max=15
isolation=random
key_gap=15
key_max=98
key_min=10
leak_memory=0
leaf_page_max=10
logging=0
logging_archive=0
logging_prealloc=0
lsm_worker_threads=4
merge_max=12
mmap=1
ops=100000
prefix_compression=1
prefix_compression_min=8
repeat_data_pct=38
reverse=0
rows=100000
runs=100
split_pct=53
statistics=0
statistics_server=0
threads=10
timer=20
value_max=3618
value_min=7
wiredtiger_config=
write_pct=13
############################################