[2025/12/17 13:25:31.499] ==================
[2025/12/17 13:25:31.499] WARNING: ThreadSanitizer: data race (pid=19709)
[2025/12/17 13:25:31.499]   Atomic write of size 8 at 0x72940000b1e8 by thread T84:
[2025/12/17 13:25:31.499]     #0 __wt_atomic_store_uint64_release /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/include/gcc.h:374:1 (libwiredtiger.so.12.0.0+0x870632)
[2025/12/17 13:25:31.499]     #1 __wt_txn_global_set_timestamp /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/txn/txn_timestamp.c:439:9 (libwiredtiger.so.12.0.0+0x871941)
[2025/12/17 13:25:31.499]     #2 __conn_set_timestamp /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/conn/conn_api.c:1427:11 (libwiredtiger.so.12.0.0+0x3372d6)
[2025/12/17 13:25:31.499]     #3 timestamp_once /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/format_timestamp.c:151:5 (t+0x100151)
[2025/12/17 13:25:31.499]     #4 timestamp /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/format_timestamp.c:199:9 (t+0x10076c)
[2025/12/17 13:25:31.499]   Previous read of size 8 at 0x72940000b1e8 by thread T81 (mutexes: write M0):
[2025/12/17 13:25:31.499]     #0 __txn_set_prepare_timestamp /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/txn/txn_timestamp.c:800:29 (libwiredtiger.so.12.0.0+0x874131)
[2025/12/17 13:25:31.499]     #1 __wt_txn_set_timestamp_uint /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/txn/txn_timestamp.c:1160:9 (libwiredtiger.so.12.0.0+0x874c20)
[2025/12/17 13:25:31.499]     #2 __session_timestamp_transaction_uint /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/session/session_api.c:2143:11 (libwiredtiger.so.12.0.0+0x71ff0c)
[2025/12/17 13:25:31.499]     #3 prepare_transaction /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/ops.c:693:5 (t+0x110227)
[2025/12/17 13:25:31.499]     #4 ops /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/ops.c:1375:24 (t+0x10ab06)
[2025/12/17 13:25:31.499]   Location is heap block of size 8512 at 0x72940000a000 allocated by main thread:
[2025/12/17 13:25:31.499]     #0 calloc /data/mci/444c1191ff66ec5bade6c97089429fd0/toolchain-builder/tmp/build-llvm-v5.sh-Dae/llvm-project-llvmorg/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:686:5 (t+0x649bb)
[2025/12/17 13:25:31.499]     #1 __wt_calloc /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/os_common/os_alloc.c:68:14 (libwiredtiger.so.12.0.0+0x5ba7c4)
[2025/12/17 13:25:31.499]     #2 wiredtiger_open /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/conn/conn_api.c:3080:5 (libwiredtiger.so.12.0.0+0x327b2e)
[2025/12/17 13:25:31.499]     #3 wts_open /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/wts.c:832:9 (t+0x1328f5)
[2025/12/17 13:25:31.499]     #4 main /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/t.c:357:9 (t+0x122ce5)
[2025/12/17 13:25:31.499]   Mutex M0 (0x7f43d0c6bdf8) created at:
[2025/12/17 13:25:31.499]     #0 pthread_mutex_init /data/mci/444c1191ff66ec5bade6c97089429fd0/toolchain-builder/tmp/build-llvm-v5.sh-Dae/llvm-project-llvmorg/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:1327:3 (t+0x67c73)
[2025/12/17 13:25:31.499]     #1 __wt_spin_init /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/include/mutex_inline.h:142:5 (libwiredtiger.so.12.0.0+0x739711)
[2025/12/17 13:25:31.499]     #2 __open_session /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/session/session_api.c:2598:5 (libwiredtiger.so.12.0.0+0x702804)
[2025/12/17 13:25:31.499]     #3 __wt_open_session /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/session/session_api.c:2721:5 (libwiredtiger.so.12.0.0+0x701fb8)
[2025/12/17 13:25:31.499]     #4 __conn_open_session /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/conn/conn_api.c:1379:5 (libwiredtiger.so.12.0.0+0x3350d2)
[2025/12/17 13:25:31.499]     #5 wt_wrap_open_session /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/format_util.c:380:5 (t+0x1027a2)
[2025/12/17 13:25:31.499]     #6 ops_session_open /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/ops.c:980:5 (t+0x10db54)
[2025/12/17 13:25:31.499]     #7 ops /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/ops.c:1088:13 (t+0x109184)
[2025/12/17 13:25:31.499]   Thread T84 (tid=19845, running) created by main thread at:
[2025/12/17 13:25:31.499]     #0 pthread_create /data/mci/444c1191ff66ec5bade6c97089429fd0/toolchain-builder/tmp/build-llvm-v5.sh-Dae/llvm-project-llvmorg/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:1023:3 (t+0x662a1)
[2025/12/17 13:25:31.499]     #1 __wt_thread_create /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/os_posix/os_thread.c:60:5 (libwiredtiger.so.12.0.0+0x5d71db)
[2025/12/17 13:25:31.499]     #2 operations /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/ops.c:383:9 (t+0x1073f2)
[2025/12/17 13:25:31.499]     #3 main /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/t.c:394:13 (t+0x1230d3)
[2025/12/17 13:25:31.499]   Thread T81 (tid=19842, running) created by main thread at:
[2025/12/17 13:25:31.499]     #0 pthread_create /data/mci/444c1191ff66ec5bade6c97089429fd0/toolchain-builder/tmp/build-llvm-v5.sh-Dae/llvm-project-llvmorg/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:1023:3 (t+0x662a1)
[2025/12/17 13:25:31.499]     #1 __wt_thread_create /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/os_posix/os_thread.c:60:5 (libwiredtiger.so.12.0.0+0x5d71db)
[2025/12/17 13:25:31.499]     #2 operations /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/ops.c:362:9 (t+0x106ee1)
[2025/12/17 13:25:31.499]     #3 main /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/test/format/t.c:394:13 (t+0x1230d3)
[2025/12/17 13:25:31.500] SUMMARY: ThreadSanitizer: data race /data/mci/eaf634bfaf712d526f52618b2cc92157/wiredtiger/src/include/gcc.h:374:1 in __wt_atomic_store_uint64_release
[2025/12/17 13:26:58.682] ==================