From 5c06e62200acc38708799b902720067a85b05087 Mon Sep 17 00:00:00 2001 From: Sam Gross Date: Thu, 16 Jul 2026 10:37:00 -0700 Subject: [PATCH] gh-149162: Use _Py_LOCK_DONT_DETACH in intern_common (gh-149164) Avoids potential deadlocks with C++ static local initialization in extensions that call PyUnicode_InternFromString during one-time initialization. (cherry picked from commit f62050d65743f0c895f7e6d665936c4e86aa39d5) Co-authored-by: Sam Gross --- .../2026-04-29-15-10-59.gh-issue-149162.BPPyrq.rst | 3 +++ Objects/unicodeobject.c | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) create mode 100644 Misc/NEWS.d/next/Core_and_Builtins/2026-04-29-15-10-59.gh-issue-149162.BPPyrq.rst diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2026-04-29-15-10-59.gh-issue-149162.BPPyrq.rst b/Misc/NEWS.d/next/Core_and_Builtins/2026-04-29-15-10-59.gh-issue-149162.BPPyrq.rst new file mode 100644 index 000000000000000..b4c443ecee07adf --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2026-04-29-15-10-59.gh-issue-149162.BPPyrq.rst @@ -0,0 +1,3 @@ +Fix a potential deadlock in :c:func:`PyUnicode_InternFromString` and other +interning functions in the :term:`free-threaded build` when called from C++ +static local initializers. diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c index 18523c2dfde77e9..c3a1beee0c8a5e7 100644 --- a/Objects/unicodeobject.c +++ b/Objects/unicodeobject.c @@ -14344,7 +14344,7 @@ intern_common(PyInterpreterState *interp, PyObject *s /* stolen */, } #endif - FT_MUTEX_LOCK(INTERN_MUTEX); + FT_MUTEX_LOCK_FLAGS(INTERN_MUTEX, _Py_LOCK_DONT_DETACH); PyObject *t; { int res = PyDict_SetDefaultRef(interned, s, s, &t);