backport: do not add the deprecated marker

Author: gpshead

Include/pythread.h

@@ -33,9 +33,9 @@ PyAPI_FUNC(unsigned long) PyThread_start_new_thread(void (*)(void *), void *);
  * destructors.
  *
  * In either case there is a risk of invalid references remaining to data on the
- * thread stack.
+ * thread stack.  This is deprecated in 3.14 onwards.  Retained for API compat.
  */
-Py_DEPRECATED(3.14) PyAPI_FUNC(void) _Py_NO_RETURN PyThread_exit_thread(void);
+PyAPI_FUNC(void) _Py_NO_RETURN PyThread_exit_thread(void);
 
 PyAPI_FUNC(unsigned long) PyThread_get_thread_ident(void);
 

Misc/NEWS.d/next/C API/2022-08-05-19-41-20.gh-issue-87135.SCNBYj.rst

@@ -5,11 +5,12 @@ terminate a thread that is running code not specifically designed to support
 termination. In most cases this hanging is harmless since the process will
 soon exit anyway.
 
-The ``PyThread_exit_thread`` function is now deprecated.  Its behavior is
-inconsistent across platforms, and it can only be used safely in the
-unlikely case that every function in the entire call stack has been designed
-to support the platform-dependent termination mechanism.  It is recommended
-that users of this function change their design to not require thread
-termination.  In the unlikely case that thread termination is needed and can
-be done safely, users may migrate to calling platform-specific APIs such as
+While not officially marked deprecated until 3.14, ``PyThread_exit_thread``
+is no longer called internally and remains solely for interface compatibility.
+Its behavior is inconsistent across platforms, and it can only be used safely
+in the unlikely case that every function in the entire call stack has been
+designed to support the platform-dependent termination mechanism.  It is
+recommended that users of this function change their design to not require
+thread termination.  In the unlikely case that thread termination is needed and
+can be done safely, users may migrate to calling platform-specific APIs such as
 ``pthread_exit`` (POSIX) or ``_endthreadex`` (Windows) directly.