intermittent issue in wallet_txn_clone.py (Windows ucrt) while starting network thread? #34367

1. 
   maflcko commented at 12:17 pm on January 21, 2026: member

   https://github.com/bitcoin/bitcoin/actions/runs/20090968443/job/57638966158?pr=32800#step:13:203:

    077/276 - wallet_txn_clone.py failed, Duration: 1 s
    1
    2stdout:
    32025-12-10T08:04:27.500134Z TestFramework (INFO): PRNG seed is: 4018092284830106117
    4
    5
    6
    7stderr:
    8
    9
   10Combine the logs and print the last 99999999 lines ...
   11
   12============
   13Combined log for D:\a\_temp/test_runner_₿_🏃_20251210_075632/wallet_txn_clone_196:
   14============
   15
   16 test  2025-12-10T08:04:27.500134Z TestFramework (INFO): PRNG seed is: 4018092284830106117 
   17 test  2025-12-10T08:04:27.500433Z TestFramework (DEBUG): Setting up network thread 
   

   Given that nothing else is printed on stdout, and stderr, the test must have failed before setup_chain, because that should log as well.

   This leaves something with the network thread. However, if the thread throws an exception, it should still print to stderr. If it kills the program silently, it seems like an upstream python bug.

2. maflcko added the label Tests on Jan 21, 2026
3. maflcko added the label CI failed on Jan 21, 2026
4. maflcko added the label Windows on Jan 21, 2026
5. 
   maflcko commented at 12:18 pm on January 21, 2026: member

   So this seems like an upstream Python bug.

   Closing for now, but discussion can continue, if someone finds something.

6. fanquake closed this on Jan 21, 2026

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