various wtperf segfaults

(gdb) bt

#0  __btree_tree_open_empty (session=0x7f3155c48800, op_cfg=<value optimized out>) at ../src/btree/bt_handle.c:412

WT-1  __wt_btree_open (session=0x7f3155c48800, op_cfg=<value optimized out>) at ../src/btree/bt_handle.c:105

WT-2  0x000000000046bc19 in __conn_btree_open (session=0x7f3155c48800, name=<value optimized out>, ckpt=<value optimized out>, cfg=0x0, flags=4)

    at ../src/conn/conn_dhandle.c:399

WT-3  __wt_conn_btree_get (session=0x7f3155c48800, name=<value optimized out>, ckpt=<value optimized out>, cfg=0x0, flags=4) at ../src/conn/conn_dhandle.c:451

WT-4  0x00000000004399f2 in __wt_session_get_btree (session=0x7f3155c48800, uri=0x7f3104453ee0 "file:test-000064.bf", checkpoint=0x0, cfg=0x0, flags=4)

    at ../src/session/session_dhandle.c:423

WT-5  0x000000000042f0a8 in __create_file (session=0x7f3155c48800, uri=<value optimized out>, config=<value optimized out>) at ../src/schema/schema_create.c:118

WT-6  __wt_schema_create (session=0x7f3155c48800, uri=<value optimized out>, config=<value optimized out>) at ../src/schema/schema_create.c:624

WT-7  0x0000000000436820 in __session_create (wt_session=0x7f3155c48800, uri=<value optimized out>, 

    config=0x7f3143ab1c40 ",key_format=r,value_format=1t,exclusive=true") at ../src/session/session_api.c:435

WT-8  0x000000000049297a in __wt_bloom_finalize (bloom=0x7f314382cd00) at ../src/bloom/bloom.c:211

WT-9  0x00000000004877bf in __lsm_bloom_create (session=0x7f3155c48800, lsm_tree=0x7f3155c69d00) at ../src/lsm/lsm_work_unit.c:382

WT-10 __wt_lsm_work_bloom (session=0x7f3155c48800, lsm_tree=0x7f3155c69d00) at ../src/lsm/lsm_work_unit.c:194

WT-11 0x00000000004206d4 in __lsm_worker_general_op (arg=0x7f3155c2f060) at ../src/lsm/lsm_worker.c:73

WT-12 __lsm_worker (arg=0x7f3155c2f060) at ../src/lsm/lsm_worker.c:121

WT-13 0x00007f315698dddb in start_thread (arg=0x7f314e3ff700) at pthread_create.c:301

WT-14 0x00007f31566dba1d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:115

(gdb) list

407		 * loads; set a flag that's cleared when a row is inserted into the

408		 * tree.   Objects being bulk-loaded cannot be evicted, we set it

409		 * globally, there's no point in searching empty trees for eviction.

410		 */

411		if (creation) {

412			btree->bulk_load_ok = 1;

413			__wt_btree_evictable(session, 0);

414		}

415	

416		/*

(gdb) p btree

$1 = (WT_BTREE *) 0x0