gh-88750: Remove the PYTHONTHREADDEBUG env var support. (#92509)

Remove the `PYTHONTHREADDEBUG` env var support.
Remove no-op dprintf() macro calls.

Author: gpshead

Doc/using/cmdline.rst

@@ -999,15 +999,6 @@ conflict.
 Debug-mode variables
 ~~~~~~~~~~~~~~~~~~~~
 
-.. envvar:: PYTHONTHREADDEBUG
-
-   If set, Python will print threading debug info into stdout.
-
-   Need a :ref:`debug build of Python <debug-build>`.
-
-   .. deprecated-removed:: 3.10 3.12
-
-
 .. envvar:: PYTHONDUMPREFS
 
    If set, Python will dump objects and reference counts still alive after

Doc/using/configure.rst

@@ -278,7 +278,6 @@ Effects of a debug build:
 * Add ``d`` to :data:`sys.abiflags`.
 * Add :func:`sys.gettotalrefcount` function.
 * Add :option:`-X showrefcount <-X>` command line option.
-* Add :envvar:`PYTHONTHREADDEBUG` environment variable.
 * Add support for the ``__lltrace__`` variable: enable low-level tracing in the
   bytecode evaluation loop if the variable is defined.
 * Install :ref:`debug hooks on memory allocators <default-memory-allocators>`

Lib/test/test_threading.py

@@ -945,16 +945,6 @@ def noop(): pass
             threading.Thread(target=noop).start()
             # Thread.join() is not called
 
-    @unittest.skipUnless(Py_DEBUG, 'need debug build (Py_DEBUG)')
-    def test_debug_deprecation(self):
-        # bpo-44584: The PYTHONTHREADDEBUG environment variable is deprecated
-        rc, out, err = assert_python_ok("-Wdefault", "-c", "pass",
-                                        PYTHONTHREADDEBUG="1")
-        msg = (b'DeprecationWarning: The threading debug '
-               b'(PYTHONTHREADDEBUG environment variable) '
-               b'is deprecated and will be removed in Python 3.12')
-        self.assertIn(msg, err)
-
     def test_import_from_another_thread(self):
         # bpo-1596321: If the threading module is first import from a thread
         # different than the main thread, threading._shutdown() must handle

Misc/NEWS.d/next/Core and Builtins/2022-05-08-19-43-31.gh-issue-88750.1BjJg-.rst

@@ -0,0 +1,2 @@
+The deprecated debug build only ``PYTHONTHREADDEBUG`` environment variable
+no longer does anything.

Misc/python.man

@@ -560,9 +560,6 @@ can be set to the callable of your debugger of choice.
 Setting these variables only has an effect in a debug build of Python, that is,
 if Python was configured with the
 \fB\--with-pydebug\fP build option.
-.IP PYTHONTHREADDEBUG
-If this environment variable is set, Python will print threading debug info.
-The feature is deprecated in Python 3.10 and will be removed in Python 3.12.
 .IP PYTHONDUMPREFS
 If this environment variable is set, Python will dump objects and reference
 counts still alive after shutting down the interpreter.

Python/pylifecycle.c

@@ -1091,8 +1091,6 @@ pyinit_main_reconfigure(PyThreadState *tstate)
 static PyStatus
 init_interp_main(PyThreadState *tstate)
 {
-    extern void _PyThread_debug_deprecation(void);
-
     assert(!_PyErr_Occurred(tstate));
 
     PyStatus status;
@@ -1194,9 +1192,6 @@ init_interp_main(PyThreadState *tstate)
 #endif
     }
 
-    // Warn about PYTHONTHREADDEBUG deprecation
-    _PyThread_debug_deprecation();
-
     assert(!_PyErr_Occurred(tstate));
 
     return _PyStatus_OK();

Python/thread.c

@@ -42,57 +42,19 @@
 
 #endif /* _POSIX_THREADS */
 
-
-#ifdef Py_DEBUG
-static int thread_debug = 0;
-#  define dprintf(args)   (void)((thread_debug & 1) && printf args)
-#else
-#  define dprintf(args)
-#endif
-
 static int initialized;
 
 static void PyThread__init_thread(void); /* Forward */
 
 void
 PyThread_init_thread(void)
 {
-#ifdef Py_DEBUG
-    const char *p = Py_GETENV("PYTHONTHREADDEBUG");
-
-    if (p) {
-        if (*p)
-            thread_debug = atoi(p);
-        else
-            thread_debug = 1;
-    }
-#endif /* Py_DEBUG */
     if (initialized)
         return;
     initialized = 1;
-    dprintf(("PyThread_init_thread called\n"));
     PyThread__init_thread();
 }
 
-void
-_PyThread_debug_deprecation(void)
-{
-#ifdef Py_DEBUG
-    if (thread_debug) {
-        // Flush previous dprintf() logs
-        fflush(stdout);
-        if (PyErr_WarnEx(PyExc_DeprecationWarning,
-                         "The threading debug (PYTHONTHREADDEBUG environment "
-                         "variable) is deprecated and will be removed "
-                         "in Python 3.12",
-                         0))
-        {
-            _PyErr_WriteUnraisableMsg("at Python startup", NULL);
-        }
-    }
-#endif
-}
-
 #if defined(_POSIX_THREADS)
 #   define PYTHREAD_NAME "pthread"
 #   include "thread_pthread.h"

Python/thread_nt.h

@@ -188,8 +188,6 @@ PyThread_start_new_thread(void (*func)(void *), void *arg)
     unsigned threadID;
     callobj *obj;
 
-    dprintf(("%lu: PyThread_start_new_thread called\n",
-             PyThread_get_thread_ident()));
     if (!initialized)
         PyThread_init_thread();
 
@@ -209,14 +207,10 @@ PyThread_start_new_thread(void (*func)(void *), void *arg)
          * too many threads".
          */
         int e = errno;
-        dprintf(("%lu: PyThread_start_new_thread failed, errno %d\n",
-                 PyThread_get_thread_ident(), e));
         threadID = (unsigned)-1;
         HeapFree(GetProcessHeap(), 0, obj);
     }
     else {
-        dprintf(("%lu: PyThread_start_new_thread succeeded: %p\n",
-                 PyThread_get_thread_ident(), (void*)hThread));
         CloseHandle(hThread);
     }
     return threadID;
@@ -257,7 +251,6 @@ PyThread_get_thread_native_id(void)
 void _Py_NO_RETURN
 PyThread_exit_thread(void)
 {
-    dprintf(("%lu: PyThread_exit_thread called\n", PyThread_get_thread_ident()));
     if (!initialized)
         exit(0);
     _endthreadex(0);
@@ -273,22 +266,17 @@ PyThread_allocate_lock(void)
 {
     PNRMUTEX aLock;
 
-    dprintf(("PyThread_allocate_lock called\n"));
     if (!initialized)
         PyThread_init_thread();
 
     aLock = AllocNonRecursiveMutex() ;
 
-    dprintf(("%lu: PyThread_allocate_lock() -> %p\n", PyThread_get_thread_ident(), aLock));
-
     return (PyThread_type_lock) aLock;
 }
 
 void
 PyThread_free_lock(PyThread_type_lock aLock)
 {
-    dprintf(("%lu: PyThread_free_lock(%p) called\n", PyThread_get_thread_ident(),aLock));
-
     FreeNonRecursiveMutex(aLock) ;
 }
 
@@ -333,9 +321,6 @@ PyThread_acquire_lock_timed(PyThread_type_lock aLock,
         milliseconds = INFINITE;
     }
 
-    dprintf(("%lu: PyThread_acquire_lock_timed(%p, %lld) called\n",
-             PyThread_get_thread_ident(), aLock, microseconds));
-
     if (aLock && EnterNonRecursiveMutex((PNRMUTEX)aLock,
                                         (DWORD)milliseconds) == WAIT_OBJECT_0) {
         success = PY_LOCK_ACQUIRED;
@@ -344,9 +329,6 @@ PyThread_acquire_lock_timed(PyThread_type_lock aLock,
         success = PY_LOCK_FAILURE;
     }
 
-    dprintf(("%lu: PyThread_acquire_lock(%p, %lld) -> %d\n",
-             PyThread_get_thread_ident(), aLock, microseconds, success));
-
     return success;
 }
 int
@@ -358,10 +340,9 @@ PyThread_acquire_lock(PyThread_type_lock aLock, int waitflag)
 void
 PyThread_release_lock(PyThread_type_lock aLock)
 {
-    dprintf(("%lu: PyThread_release_lock(%p) called\n", PyThread_get_thread_ident(),aLock));
-
-    if (!(aLock && LeaveNonRecursiveMutex((PNRMUTEX) aLock)))
-        dprintf(("%lu: Could not PyThread_release_lock(%p) error: %ld\n", PyThread_get_thread_ident(), aLock, GetLastError()));
+    if (aLock) {
+        (void)LeaveNonRecursiveMutex((PNRMUTEX) aLock);
+    }
 }
 
 /* minimum/maximum thread stack sizes supported */

Python/thread_pthread.h

@@ -252,7 +252,6 @@ PyThread_start_new_thread(void (*func)(void *), void *arg)
     size_t      tss;
 #endif
 
-    dprintf(("PyThread_start_new_thread called\n"));
     if (!initialized)
         PyThread_init_thread();
 
@@ -358,7 +357,6 @@ PyThread_get_thread_native_id(void)
 void _Py_NO_RETURN
 PyThread_exit_thread(void)
 {
-    dprintf(("PyThread_exit_thread called\n"));
     if (!initialized)
         exit(0);
     pthread_exit(0);
@@ -376,7 +374,6 @@ PyThread_allocate_lock(void)
     sem_t *lock;
     int status, error = 0;
 
-    dprintf(("PyThread_allocate_lock called\n"));
     if (!initialized)
         PyThread_init_thread();
 
@@ -392,7 +389,6 @@ PyThread_allocate_lock(void)
         }
     }
 
-    dprintf(("PyThread_allocate_lock() -> %p\n", (void *)lock));
     return (PyThread_type_lock)lock;
 }
 
@@ -403,7 +399,6 @@ PyThread_free_lock(PyThread_type_lock lock)
     int status, error = 0;
 
     (void) error; /* silence unused-but-set-variable warning */
-    dprintf(("PyThread_free_lock(%p) called\n", lock));
 
     if (!thelock)
         return;
@@ -435,8 +430,6 @@ PyThread_acquire_lock_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds,
     int status, error = 0;
 
     (void) error; /* silence unused-but-set-variable warning */
-    dprintf(("PyThread_acquire_lock_timed(%p, %lld, %d) called\n",
-             lock, microseconds, intr_flag));
 
     _PyTime_t timeout;  // relative timeout
     if (microseconds >= 0) {
@@ -544,8 +537,6 @@ PyThread_acquire_lock_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds,
         success = PY_LOCK_FAILURE;
     }
 
-    dprintf(("PyThread_acquire_lock_timed(%p, %lld, %d) -> %d\n",
-             lock, microseconds, intr_flag, success));
     return success;
 }
 
@@ -556,7 +547,6 @@ PyThread_release_lock(PyThread_type_lock lock)
     int status, error = 0;
 
     (void) error; /* silence unused-but-set-variable warning */
-    dprintf(("PyThread_release_lock(%p) called\n", lock));
 
     status = sem_post(thelock);
     CHECK_STATUS("sem_post");
@@ -573,7 +563,6 @@ PyThread_allocate_lock(void)
     pthread_lock *lock;
     int status, error = 0;
 
-    dprintf(("PyThread_allocate_lock called\n"));
     if (!initialized)
         PyThread_init_thread();
 
@@ -599,7 +588,6 @@ PyThread_allocate_lock(void)
         }
     }
 
-    dprintf(("PyThread_allocate_lock() -> %p\n", (void *)lock));
     return (PyThread_type_lock) lock;
 }
 
@@ -610,7 +598,6 @@ PyThread_free_lock(PyThread_type_lock lock)
     int status, error = 0;
 
     (void) error; /* silence unused-but-set-variable warning */
-    dprintf(("PyThread_free_lock(%p) called\n", lock));
 
     /* some pthread-like implementations tie the mutex to the cond
      * and must have the cond destroyed first.
@@ -632,9 +619,6 @@ PyThread_acquire_lock_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds,
     pthread_lock *thelock = (pthread_lock *)lock;
     int status, error = 0;
 
-    dprintf(("PyThread_acquire_lock_timed(%p, %lld, %d) called\n",
-             lock, microseconds, intr_flag));
-
     if (microseconds == 0) {
         status = pthread_mutex_trylock( &thelock->mut );
         if (status != EBUSY)
@@ -694,8 +678,6 @@ PyThread_acquire_lock_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds,
     }
 
     if (error) success = PY_LOCK_FAILURE;
-    dprintf(("PyThread_acquire_lock_timed(%p, %lld, %d) -> %d\n",
-             lock, microseconds, intr_flag, success));
     return success;
 }
 
@@ -706,7 +688,6 @@ PyThread_release_lock(PyThread_type_lock lock)
     int status, error = 0;
 
     (void) error; /* silence unused-but-set-variable warning */
-    dprintf(("PyThread_release_lock(%p) called\n", lock));
 
     status = pthread_mutex_lock( &thelock->mut );
     CHECK_STATUS_PTHREAD("pthread_mutex_lock[3]");