Issues

Issues

• [BUG]: Data race in class_::init_instance() on free-threaded builds

  pybind/pybind11#6214 · opened on Oct 24, 2026

• [BUG]: Repeated gil_scoped_acquire in a persistent C++ thread pool causes a PyThreadState_Clear hotspot on free-threaded CPython 3.14

  pybind/pybind11#6179 · opened on Sep 16, 2026
  1

• [BUG]: Intermittent null internals_pp_manager::get_pp() during concurrent subinterpreter imports on Windows

  pybind/pybind11#6174 · opened on Sep 12, 2026
  1

• [BUG]: -Wmaybe-uninitialized warnings in O3 optimization

  pybind/pybind11#6167 · opened on Sep 2, 2026

• Fable 5.1 review of pybind11

  pybind/pybind11#6159 · opened on Sep 1, 2026
  3

• Untrusted impersonation of the project at pybind11.com

  pybind/pybind11#6076 · opened on May 23, 2026

• Collecting subinterpreter-related CI flakes

  pybind/pybind11#6071 · opened on May 18, 2026
  3

• [BUG]: cmake: pybind11::embed target doesn't link to Python libs if find_package(Python) has been called previously

  pybind/pybind11#6063 · opened on May 14, 2026

• [BUG]: Document MSVC std::mutex ABI hazard with older msvcp140.dll and _DISABLE_CONSTEXPR_MUTEX_CONSTRUCTOR

  pybind/pybind11#6053 · opened on May 4, 2026

• [BUG]: nullptr dereference in create_pp_content_once (internals.h)

  pybind/pybind11#6046 · opened on Apr 30, 2026

• [BUG]: 5 tests fail

  pybind/pybind11#6037 · opened on Apr 14, 2026

• [BUG]: "Already defined" import error when reusing a value name in different enums

  pybind/pybind11#6031 · opened on Apr 7, 2026

• [BUG]: Objects created using __new__ are not registered for casting

  pybind/pybind11#6025 · opened on Mar 30, 2026

• [BUG]: std::move_constructible and pybind11::detail::is_move_constructible differ

  pybind/pybind11#5983 · opened on Feb 8, 2026
  1

• [BUG]: Hijacked domain is confusing

  pybind/pybind11#5963 · opened on Jan 18, 2026

• [BUG]: Security link goes nowhere

  pybind/pybind11#5962 · opened on Jan 18, 2026

• [BUG]: Compilation failure with MSVC 17.12 (v14.44) and C++20: '_BACKUP_ITERATOR_DEBUG_LEVEL' undeclared

  pybind/pybind11#5956 · opened on Jan 9, 2026

• [BUG]: Cross compilation (x86_64-linux -> armv7l) fails with LONG_BIT related errors

  pybind/pybind11#5945 · opened on Dec 24, 2025

• [BUG]: CMake add_subdirectory() interference from system-installed pybind11

  pybind/pybind11#5937 · opened on Dec 15, 2025
  1

• [BUG]: integral caster inconsistencies

  pybind/pybind11#5895 · opened on Nov 12, 2025

• [BUG]: py::py::mod_gil_not_used() maybe not support python 3.14.0 free threaded feature, when using callback function

  pybind/pybind11#5894 · opened on Nov 12, 2025

• [BUG]: KeysView/ItemsView does not support set operations

  pybind/pybind11#5876 · opened on Oct 21, 2025

• [BUG]: 5 tests fail on FreeBSD

  pybind/pybind11#5872 · opened on Oct 15, 2025

• [BUG]: This PR addresses recurring C4819 compiler warnings on Windows when using pybind11 with non-Unicode code pages (e.g., CP936):

  pybind/pybind11#5863 · opened on Oct 12, 2025

• [BUG]: Misleading errors on duplicate enum key registration

  pybind/pybind11#5853 · opened on Oct 1, 2025