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merkle: pre‑reserve leaves to prevent reallocs with odd vtx count #14

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@l0rinc l0rinc commented May 12, 2025

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@l0rinc l0rinc changed the title merkle: reserve leaves to even before ComputeMerkleRoot call merkle: pre‑reserve leaves to prevent reallocs with odd vtx count May 12, 2025
@l0rinc l0rinc force-pushed the detached262 branch 2 times, most recently from 1edeecc to 7196a59 Compare May 12, 2025 16:38
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l0rinc commented May 13, 2025

With

        if (hashes.size() & 1) {
            assert(hashes.size() < hashes.capacity()); // TODO remove
            hashes.push_back(hashes.back());
        }

and

    leaves.reserve((block.vtx.size() + 1) & ~1ULL); // capacity rounded up to even
    leaves.emplace_back();
    assert(leaves.back().IsNull()); // TODO remove
COMMITS="8713edceff688f023593c0e380d09adef79095fa"; \
STOP_HEIGHT=896408; DBCACHE=4500; \
CC=gcc; CXX=g++; \
BASE_DIR="/mnt/my_storage"; DATA_DIR="$BASE_DIR/BitcoinData"; LOG_DIR="$BASE_DIR/logs"; \
(echo ""; for c in $COMMITS; do git fetch origin $c -q && git log -1 --pretty=format:'%h %s' $c || exit 1; done; echo "") && \
hyperfine \
  --sort 'command' \
  --runs 1 \
  --export-json "$BASE_DIR/rdx-$(sed -E 's/(\w{8})\w+ ?/\1-/g; s/-$//' <<< "$COMMITS")-$STOP_HEIGHT-$DBCACHE-$CC.json" \
  --parameter-list COMMIT ${COMMITS// /,} \
  --prepare "killall bitcoind; rm -f $DATA_DIR/debug.log; git checkout {COMMIT}; git clean -fxd; git reset --hard; \
    cmake -B build -DCMAKE_BUILD_TYPE=Release -DENABLE_WALLET=OFF && cmake --build build -j$(nproc) --target bitcoind && \
    ./build/bin/bitcoind -datadir=$DATA_DIR -stopatheight=$STOP_HEIGHT -dbcache=5000 -printtoconsole=0; sleep 10" \
  --cleanup "cp $DATA_DIR/debug.log $LOG_DIR/debug-{COMMIT}-$(date +%s).log" \
  "COMPILER=$CC ./build/bin/bitcoind -datadir=$DATA_DIR -stopatheight=$STOP_HEIGHT -reindex-chainstate -blocksonly -connect=0 -printtoconsole=0 -dbcache=$DBCACHE"

8713edceff merkle: reserve leaves to even before `ComputeMerkleRoot` call

Benchmark 1: COMPILER=gcc ./build/bin/bitcoind -datadir=/mnt/my_storage/BitcoinData -stopatheight=896408 -reindex-chainstate -blocksonly -connect=0 -printtoconsole=0 -dbcache=4500 (COMMIT = 8713edceff688f023593c0e380d09adef79095fa)
  Time (abs ≡):        26388.120 s               [User: 28537.493 s, System: 919.613 s]

@l0rinc l0rinc closed this May 14, 2025
l0rinc pushed a commit that referenced this pull request Jun 25, 2025
@fanquake
lsan: add more Qt suppressions
5be31b2 
Using Clang clang version 20.1.6 (Fedora 20.1.6-9.fc43) and:
```bash
export CC=clang
export CXX=clang++
cmake -B build -DBUILD_GUI=ON -DSANITIZERS=address
cmake --build build
export LSAN_OPTIONS="suppressions=/root/bitcoin/test/sanitizer_suppressions/lsan"
ctest --test-dir build
```

```bash
Totals: 3 passed, 0 failed, 0 skipped, 0 blacklisted, 1589ms
********* Finished testing of AddressBookTests *********

=================================================================
==21869==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 88 byte(s) in 1 object(s) allocated from:
    #0 0xaaaab5d5af40 in operator new(unsigned long) (/root/bitcoin/build/bin/test_bitcoin-qt+0x39af40) (BuildId: c0e038f1c507ea6860d1cfd499ac54ad83359872)
    #1 0xffff8c8f56cc in QLayoutPrivate::createWidgetItem(QLayout const*, QWidget*) (/lib64/libQt6Widgets.so.6+0x1a56cc) (BuildId: 8b7b9e470f4d4cd920282a4f963abb01225814fa)
    #2 0xffff8c8d2f90 in QBoxLayout::insertWidget(int, QWidget*, int, QFlags<Qt::AlignmentFlag>) (/lib64/libQt6Widgets.so.6+0x182f90) (BuildId: 8b7b9e470f4d4cd920282a4f963abb01225814fa)
    #3 0xaaaab5fc7188 in SendCoinsDialog::addEntry() /root/bitcoin/build/src/qt/./qt/sendcoinsdialog.cpp:596:18
    #4 0xaaaab5fc4eec in SendCoinsDialog::SendCoinsDialog(PlatformStyle const*, QWidget*) /root/bitcoin/build/src/qt/./qt/sendcoinsdialog.cpp:84:5
    #5 0xaaaab5da67ac in (anonymous namespace)::MiniGUI::MiniGUI(interfaces::Node&, PlatformStyle const*) /root/bitcoin/build/src/qt/test/./qt/test/wallettests.cpp:235:75
    #6 0xaaaab5da2000 in (anonymous namespace)::TestGUI(interfaces::Node&, std::shared_ptr<wallet::CWallet> const&) /root/bitcoin/build/src/qt/test/./qt/test/wallettests.cpp:270:13
    #7 0xaaaab5d9ebc8 in (anonymous namespace)::TestGUI(interfaces::Node&) /root/bitcoin/build/src/qt/test/./qt/test/wallettests.cpp:453:5
    #8 0xaaaab5d9ebc8 in WalletTests::walletTests() /root/bitcoin/build/src/qt/test/./qt/test/wallettests.cpp:475:5
    #9 0xffff8b1c5314 in QMetaMethodInvoker::invokeImpl(QMetaMethod, void*, Qt::ConnectionType, long long, void const* const*, char const* const*, QtPrivate::QMetaTypeInterface const* const*) (/lib64/libQt6Core.so.6+0x195314) (BuildId: eacb2d1228362560e5df1a1ce496c99ad61960e7)
    #10 0xffff8b1c5dc8 in QMetaMethod::invokeImpl(QMetaMethod, void*, Qt::ConnectionType, long long, void const* const*, char const* const*, QtPrivate::QMetaTypeInterface const* const*) (/lib64/libQt6Core.so.6+0x195dc8) (BuildId: eacb2d1228362560e5df1a1ce496c99ad61960e7)
    #11 0xffff8cf57c54  (/lib64/libQt6Test.so.6+0x27c54) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
    #12 0xffff8cf5fa18  (/lib64/libQt6Test.so.6+0x2fa18) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
    #13 0xffff8cf6067c  (/lib64/libQt6Test.so.6+0x3067c) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
    #14 0xffff8cf610a4  (/lib64/libQt6Test.so.6+0x310a4) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
    #15 0xffff8cf61aa4 in QTest::qRun() (/lib64/libQt6Test.so.6+0x31aa4) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
    #16 0xffff8cf61eb4 in QTest::qExec(QObject*, int, char**) (/lib64/libQt6Test.so.6+0x31eb4) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
    #17 0xaaaab5d7d77c in main /root/bitcoin/build/src/qt/test/./qt/test/test_main.cpp:95:30
    #18 0xffff8aad6398 in __libc_start_call_main (/lib64/libc.so.6+0x26398) (BuildId: 627f878dd454ee3cc1dfdbd347bb565f1ffb53e7)
    #19 0xffff8aad6478 in __libc_start_main@GLIBC_2.17 (/lib64/libc.so.6+0x26478) (BuildId: 627f878dd454ee3cc1dfdbd347bb565f1ffb53e7)
    #20 0xaaaab5c74cac in _start (/root/bitcoin/build/bin/test_bitcoin-qt+0x2b4cac) (BuildId: c0e038f1c507ea6860d1cfd499ac54ad83359872)
```

This happens when building using depends:
```bash
Indirect leak of 24 byte(s) in 1 object(s) allocated from:
    #0 0xaaaabdbe86f8 in malloc (/root/bitcoin/build/bin/test_bitcoin-qt+0x4386f8) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #1 0xfbff97f8c164  (<unknown module>)
    #2 0xaaaabf0cfaa4 in QDBusConnectionPrivate::QDBusConnectionPrivate() (/root/bitcoin/build/bin/test_bitcoin-qt+0x191faa4) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #3 0xaaaabf0c9e30 in QDBusConnectionManager::doConnectToStandardBus(QDBusConnection::BusType, QString const&, bool) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1919e30) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #4 0xaaaabf0cb0e4 in QtPrivate::QCallableObject<QDBusConnectionPrivate* (QDBusConnectionManager::*)(QDBusConnection::BusType, QString const&, bool), QtPrivate::List<QDBusConnection::BusType&, QString const&, bool&>, QDBusConnectionPrivate*>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x191b0e4) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #5 0xaaaabf5cbaf0 in QObject::event(QEvent*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1e1baf0) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #6 0xaaaabf5a4ce0 in QCoreApplicationPrivate::notify_helper(QObject*, QEvent*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1df4ce0) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #7 0xaaaabf5a486c in QCoreApplication::notifyInternal2(QObject*, QEvent*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1df486c) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #8 0xaaaabf5a575c in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1df575c) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #9 0xaaaabf66b858 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1ebb858) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #10 0xaaaabf5a9e3c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1df9e3c) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #11 0xaaaabf632a44 in QThread::exec() (/root/bitcoin/build/bin/test_bitcoin-qt+0x1e82a44) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #12 0xaaaabf0c9bd0 in QDBusConnectionManager::run() (/root/bitcoin/build/bin/test_bitcoin-qt+0x1919bd0) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #13 0xaaaabf669c30 in QThreadPrivate::start(void*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1eb9c30) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
    #14 0xaaaabdbe5f2c in asan_thread_start(void*) asan_interceptors.cpp.o
    #15 0xffff99538608 in thread_start (/lib64/libc.so.6+0xf8608) (BuildId: 627f878dd454ee3cc1dfdbd347bb565f1ffb53e7)

SUMMARY: AddressSanitizer: 3592 byte(s) leaked in 37 allocation(s).
```
l0rinc pushed a commit that referenced this pull request Jun 25, 2025
@fanquake
Merge bitcoin#32780: lsan: add more Qt suppressions
67e6746 
5be31b2 lsan: add more Qt suppressions (fanquake)

Pull request description:

  Using Clang clang version 20.1.6 (Fedora 20.1.6-9.fc43) and:
  ```bash
  export CC=clang
  export CXX=clang++
  cmake -B build -DBUILD_GUI=ON -DSANITIZERS=address
  cmake --build build
  export LSAN_OPTIONS="suppressions=/root/bitcoin/test/sanitizer_suppressions/lsan"
  ctest --test-dir build
  ```

  ```bash
  Totals: 3 passed, 0 failed, 0 skipped, 0 blacklisted, 1589ms
  ********* Finished testing of AddressBookTests *********

  =================================================================
  ==21869==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 88 byte(s) in 1 object(s) allocated from:
      #0 0xaaaab5d5af40 in operator new(unsigned long) (/root/bitcoin/build/bin/test_bitcoin-qt+0x39af40) (BuildId: c0e038f1c507ea6860d1cfd499ac54ad83359872)
      #1 0xffff8c8f56cc in QLayoutPrivate::createWidgetItem(QLayout const*, QWidget*) (/lib64/libQt6Widgets.so.6+0x1a56cc) (BuildId: 8b7b9e470f4d4cd920282a4f963abb01225814fa)
      #2 0xffff8c8d2f90 in QBoxLayout::insertWidget(int, QWidget*, int, QFlags<Qt::AlignmentFlag>) (/lib64/libQt6Widgets.so.6+0x182f90) (BuildId: 8b7b9e470f4d4cd920282a4f963abb01225814fa)
      #3 0xaaaab5fc7188 in SendCoinsDialog::addEntry() /root/bitcoin/build/src/qt/./qt/sendcoinsdialog.cpp:596:18
      #4 0xaaaab5fc4eec in SendCoinsDialog::SendCoinsDialog(PlatformStyle const*, QWidget*) /root/bitcoin/build/src/qt/./qt/sendcoinsdialog.cpp:84:5
      #5 0xaaaab5da67ac in (anonymous namespace)::MiniGUI::MiniGUI(interfaces::Node&, PlatformStyle const*) /root/bitcoin/build/src/qt/test/./qt/test/wallettests.cpp:235:75
      #6 0xaaaab5da2000 in (anonymous namespace)::TestGUI(interfaces::Node&, std::shared_ptr<wallet::CWallet> const&) /root/bitcoin/build/src/qt/test/./qt/test/wallettests.cpp:270:13
      #7 0xaaaab5d9ebc8 in (anonymous namespace)::TestGUI(interfaces::Node&) /root/bitcoin/build/src/qt/test/./qt/test/wallettests.cpp:453:5
      #8 0xaaaab5d9ebc8 in WalletTests::walletTests() /root/bitcoin/build/src/qt/test/./qt/test/wallettests.cpp:475:5
      #9 0xffff8b1c5314 in QMetaMethodInvoker::invokeImpl(QMetaMethod, void*, Qt::ConnectionType, long long, void const* const*, char const* const*, QtPrivate::QMetaTypeInterface const* const*) (/lib64/libQt6Core.so.6+0x195314) (BuildId: eacb2d1228362560e5df1a1ce496c99ad61960e7)
      #10 0xffff8b1c5dc8 in QMetaMethod::invokeImpl(QMetaMethod, void*, Qt::ConnectionType, long long, void const* const*, char const* const*, QtPrivate::QMetaTypeInterface const* const*) (/lib64/libQt6Core.so.6+0x195dc8) (BuildId: eacb2d1228362560e5df1a1ce496c99ad61960e7)
      #11 0xffff8cf57c54  (/lib64/libQt6Test.so.6+0x27c54) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
      #12 0xffff8cf5fa18  (/lib64/libQt6Test.so.6+0x2fa18) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
      #13 0xffff8cf6067c  (/lib64/libQt6Test.so.6+0x3067c) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
      #14 0xffff8cf610a4  (/lib64/libQt6Test.so.6+0x310a4) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
      #15 0xffff8cf61aa4 in QTest::qRun() (/lib64/libQt6Test.so.6+0x31aa4) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
      #16 0xffff8cf61eb4 in QTest::qExec(QObject*, int, char**) (/lib64/libQt6Test.so.6+0x31eb4) (BuildId: 96bb1cdeead53af0ced36d7970cf9cd79c4c4ccd)
      #17 0xaaaab5d7d77c in main /root/bitcoin/build/src/qt/test/./qt/test/test_main.cpp:95:30
      #18 0xffff8aad6398 in __libc_start_call_main (/lib64/libc.so.6+0x26398) (BuildId: 627f878dd454ee3cc1dfdbd347bb565f1ffb53e7)
      #19 0xffff8aad6478 in __libc_start_main@GLIBC_2.17 (/lib64/libc.so.6+0x26478) (BuildId: 627f878dd454ee3cc1dfdbd347bb565f1ffb53e7)
      #20 0xaaaab5c74cac in _start (/root/bitcoin/build/bin/test_bitcoin-qt+0x2b4cac) (BuildId: c0e038f1c507ea6860d1cfd499ac54ad83359872)
  ```

  This happens when building using depends:
  ```bash
  Indirect leak of 24 byte(s) in 1 object(s) allocated from:
      #0 0xaaaabdbe86f8 in malloc (/root/bitcoin/build/bin/test_bitcoin-qt+0x4386f8) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #1 0xfbff97f8c164  (<unknown module>)
      #2 0xaaaabf0cfaa4 in QDBusConnectionPrivate::QDBusConnectionPrivate() (/root/bitcoin/build/bin/test_bitcoin-qt+0x191faa4) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #3 0xaaaabf0c9e30 in QDBusConnectionManager::doConnectToStandardBus(QDBusConnection::BusType, QString const&, bool) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1919e30) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #4 0xaaaabf0cb0e4 in QtPrivate::QCallableObject<QDBusConnectionPrivate* (QDBusConnectionManager::*)(QDBusConnection::BusType, QString const&, bool), QtPrivate::List<QDBusConnection::BusType&, QString const&, bool&>, QDBusConnectionPrivate*>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x191b0e4) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #5 0xaaaabf5cbaf0 in QObject::event(QEvent*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1e1baf0) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #6 0xaaaabf5a4ce0 in QCoreApplicationPrivate::notify_helper(QObject*, QEvent*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1df4ce0) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #7 0xaaaabf5a486c in QCoreApplication::notifyInternal2(QObject*, QEvent*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1df486c) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #8 0xaaaabf5a575c in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1df575c) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #9 0xaaaabf66b858 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1ebb858) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #10 0xaaaabf5a9e3c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1df9e3c) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #11 0xaaaabf632a44 in QThread::exec() (/root/bitcoin/build/bin/test_bitcoin-qt+0x1e82a44) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #12 0xaaaabf0c9bd0 in QDBusConnectionManager::run() (/root/bitcoin/build/bin/test_bitcoin-qt+0x1919bd0) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #13 0xaaaabf669c30 in QThreadPrivate::start(void*) (/root/bitcoin/build/bin/test_bitcoin-qt+0x1eb9c30) (BuildId: dd54811dc11325890f7bac3e3a49d38f5a7ffef5)
      #14 0xaaaabdbe5f2c in asan_thread_start(void*) asan_interceptors.cpp.o
      #15 0xffff99538608 in thread_start (/lib64/libc.so.6+0xf8608) (BuildId: 627f878dd454ee3cc1dfdbd347bb565f1ffb53e7)

  SUMMARY: AddressSanitizer: 3592 byte(s) leaked in 37 allocation(s).
  ```

ACKs for top commit:
  maflcko:
    lgtm ACK 5be31b2

Tree-SHA512: 0c33661c7ec83ea9b874c1ee4ee2de513131690287363e216a88560dfb31a59ef563a50af756c86a991583aa64a600a74e20fd5d6a104cf4c0a27532de8d2211
l0rinc pushed a commit that referenced this pull request Jul 28, 2025
@fanquake
Merge bitcoin#33063: util: Revert "common: Close non-std fds before e…
75a5c82 
…xec in RunCommandJSON"

faa1c3e Revert "Merge bitcoin#32343: common: Close non-std fds before exec in RunCommandJSON" (MarcoFalke)

Pull request description:

  After a fork() in a multithreaded program, the child can safely
  call only async-signal-safe functions (see [signal-safety(7)](https://www.man7.org/linux/man-pages/man7/signal-safety.7.html))
  until such time as it calls execv.

  The standard library (`std` namespace) is not async-signal-safe. Also, `throw`, isn't.

  There was an alternative implementation using `readdir` (bitcoin#32529), but that isn't async-signal-safe either, and that implementation was still using `throw`.

  So temporarily revert this feature.

  A follow-up in the future can add it back, using only async-signal-safe functions, or by using a different approach.

  Fixes bitcoin#32524
  Fixes bitcoin#33015
  Fixes bitcoin#32855

  For reference, a failure can manifest in the GCC debug mode:

  * While `fork`ing, a debug mode mutex is held (by any other thread).
  * The `fork`ed child tries to use the stdard libary before `execv` and deadlocks.

  This may look like the following:

  ```
  (gdb) thread apply all bt

  Thread 1 (Thread 0xf58f4b40 (LWP 774911) "b-httpworker.2"):
  #0  0xf7f4f589 in __kernel_vsyscall ()
  #1  0xf79e467e in ?? () from /lib32/libc.so.6
  #2  0xf79eb582 in pthread_mutex_lock () from /lib32/libc.so.6
  #3  0xf7d93bf2 in ?? () from /lib32/libstdc++.so.6
  #4  0xf7d93f36 in __gnu_debug::_Safe_iterator_base::_M_attach(__gnu_debug::_Safe_sequence_base*, bool) () from /lib32/libstdc++.so.6
  #5  0x5668810a in __gnu_debug::_Safe_iterator_base::_Safe_iterator_base (this=0xf58f13ac, __seq=0xf58f13f8, __constant=false) at /bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/debug/safe_base.h:91
  #6  0x56ddfb50 in __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<int*, std::__cxx1998::vector<int, std::allocator<int> > >, std::__debug::vector<int, std::allocator<int> >, std::forward_iterator_tag>::_Safe_iterator (this=0xf58f13a8, __i=3, __seq=0xf58f13f8) at /bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/debug/safe_iterator.h:162
  #7  0x56ddfacb in __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<int*, std::__cxx1998::vector<int, std::allocator<int> > >, std::__debug::vector<int, std::allocator<int> >, std::bidirectional_iterator_tag>::_Safe_iterator (this=0xf58f13a8, __i=3, __seq=0xf58f13f8) at /bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/debug/safe_iterator.h:539
  #8  0x56ddfa5b in __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<int*, std::__cxx1998::vector<int, std::allocator<int> > >, std::__debug::vector<int, std::allocator<int> >, std::random_access_iterator_tag>::_Safe_iterator (this=0xf58f13a8, __i=3, __seq=0xf58f13f8) at /bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/debug/safe_iterator.h:687
  #9  0x56ddd3f6 in std::__debug::vector<int, std::allocator<int> >::begin (this=0xf58f13f8) at /bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/debug/vector:300
  #10 0x57d83701 in subprocess::detail::Child::execute_child (this=0xf58f156c) at ./util/subprocess.h:1372
  #11 0x57d80a7c in subprocess::Popen::execute_process (this=0xf58f1cd8) at ./util/subprocess.h:1231
  #12 0x57d6d2b4 in subprocess::Popen::Popen<subprocess::input, subprocess::output, subprocess::error, subprocess::close_fds> (this=0xf58f1cd8, cmd_args="fake.py enumerate", args=..., args=..., args=..., args=...) at ./util/subprocess.h:964
  #13 0x57d6b597 in RunCommandParseJSON (str_command="fake.py enumerate", str_std_in="") at ./common/run_command.cpp:27
  #14 0x57a90547 in ExternalSigner::Enumerate (command="fake.py", signers=std::__debug::vector of length 0, capacity 0, chain="regtest") at ./external_signer.cpp:28
  #15 0x56defdab in enumeratesigners()::$_0::operator()(RPCHelpMan const&, JSONRPCRequest const&) const (this=0xf58f2ba0, self=..., request=...) at ./rpc/external_signer.cpp:51
  ...
  (truncated, only one thread exists)
  ```

ACKs for top commit:
  fanquake:
    ACK faa1c3e
  darosior:
    ACK faa1c3e

Tree-SHA512: 602da5f2eba08d7fe01ba19baf411e287ae27fe2d4b82f41734e05b7b1d938ce94cc0041e86ba677284fa92838e96ebee687023ff28047e2b036fd9a53567e0a
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@l0rinc