Issue #21963: backout issue #1856 patch (avoid crashes and lockups when

daemon threads run while the interpreter is shutting down; instead,
these threads are now killed when they try to take the GIL), as it seems
to break some existing code.

3 files changed, 3 insertions, 22 deletions

diff --git a/Python/ceval.c b/Python/ceval.c
index dad5e1c..682a1e7 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -355,12 +355,6 @@ PyEval_RestoreThread(PyThreadState *tstate)
     if (interpreter_lock) {
         int err = errno;
         PyThread_acquire_lock(interpreter_lock, 1);
-        /* _Py_Finalizing is protected by the GIL */
-        if (_Py_Finalizing && tstate != _Py_Finalizing) {
-            PyThread_release_lock(interpreter_lock);
-            PyThread_exit_thread();
-            assert(0);  /* unreachable */
-        }
         errno = err;
     }
 #endif
@@ -1025,12 +1019,6 @@ PyEval_EvalFrameEx(PyFrameObject *f, int throwflag)
 
                 PyThread_acquire_lock(interpreter_lock, 1);
 
-                /* Check if we should make a quick exit. */
-                if (_Py_Finalizing && _Py_Finalizing != tstate) {
-                    PyThread_release_lock(interpreter_lock);
-                    PyThread_exit_thread();
-                }
-
                 if (PyThreadState_Swap(tstate) != NULL)
                     Py_FatalError("ceval: orphan tstate");
 
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index 05bb62b..ade5efe 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -91,8 +91,6 @@ int _Py_QnewFlag = 0;
 int Py_NoUserSiteDirectory = 0; /* for -s and site.py */
 int Py_HashRandomizationFlag = 0; /* for -R and PYTHONHASHSEED */
 
-PyThreadState *_Py_Finalizing = NULL;
-
 
 /* Hack to force loading of object files */
 int (*_PyOS_mystrnicmp_hack)(const char *, const char *, Py_ssize_t) = \
@@ -165,7 +163,6 @@ Py_InitializeEx(int install_sigs)
     if (initialized)
         return;
     initialized = 1;
-    _Py_Finalizing = NULL;
 
     if ((p = Py_GETENV("PYTHONDEBUG")) && *p != '\0')
         Py_DebugFlag = add_flag(Py_DebugFlag, p);
@@ -425,16 +422,12 @@ Py_Finalize(void)
      * the threads created via Threading.
      */
     call_sys_exitfunc();
+    initialized = 0;
 
     /* Get current thread state and interpreter pointer */
     tstate = PyThreadState_GET();
     interp = tstate->interp;
 
-    /* Remaining threads (e.g. daemon threads) will automatically exit
-       after taking the GIL (in PyEval_RestoreThread()). */
-    _Py_Finalizing = tstate;
-    initialized = 0;
-
     /* Disable signal handling */
     PyOS_FiniInterrupts();
 
diff --git a/Python/thread_pthread.h b/Python/thread_pthread.h
index 0c1fdfe..c9ed796 100644
--- a/Python/thread_pthread.h
+++ b/Python/thread_pthread.h
@@ -242,9 +242,9 @@ void
 PyThread_exit_thread(void)
 {
     dprintf(("PyThread_exit_thread called\n"));
-    if (!initialized)
+    if (!initialized) {
         exit(0);
-    pthread_exit(0);
+    }
 }
 
 #ifdef USE_SEMAPHORES