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Issue #9670: merge with 3.2
2 parents 226580e + 517ac72 commit 15012a6

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Lib/test/test_threading.py

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@@ -677,6 +677,36 @@ def test_daemonize_active_thread(self):
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thread.start()
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self.assertRaises(RuntimeError, setattr, thread, "daemon", True)
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def test_recursion_limit(self):
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# Issue 9670
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# test that excessive recursion within a non-main thread causes
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# an exception rather than crashing the interpreter on platforms
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# like Mac OS X or FreeBSD which have small default stack sizes
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# for threads
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script = """if True:
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import threading
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def recurse():
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return recurse()
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def outer():
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try:
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recurse()
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except RuntimeError:
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pass
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w = threading.Thread(target=outer)
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w.start()
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w.join()
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print('end of main thread')
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"""
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expected_output = "end of main thread\n"
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p = subprocess.Popen([sys.executable, "-c", script],
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stdout=subprocess.PIPE)
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stdout, stderr = p.communicate()
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data = stdout.decode().replace('\r', '')
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self.assertEqual(p.returncode, 0, "Unexpected error")
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self.assertEqual(data, expected_output)
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class LockTests(lock_tests.LockTests):
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locktype = staticmethod(threading.Lock)

Misc/NEWS

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@@ -10,6 +10,11 @@ What's New in Python 3.2.1?
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Core and Builtins
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-----------------
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- Issue #9670: Increase the default stack size for secondary threads on
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Mac OS X and FreeBSD to reduce the chances of a crash instead of a
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"maximum recursion depth" RuntimeError exception.
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(original patch by Ronald Oussoren)
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- Issue #11650: PyOS_StdioReadline() retries fgets() if it was interrupted
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(EINTR), for example if the program is stopped with CTRL+z on Mac OS X. Patch
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written by Charles-Francois Natali.

Python/thread_pthread.h

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@@ -18,6 +18,18 @@
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#ifndef THREAD_STACK_SIZE
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#define THREAD_STACK_SIZE 0 /* use default stack size */
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#endif
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#if (defined(__APPLE__) || defined(__FreeBSD__)) && defined(THREAD_STACK_SIZE) && THREAD_STACK_SIZE == 0
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/* The default stack size for new threads on OSX is small enough that
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* we'll get hard crashes instead of 'maximum recursion depth exceeded'
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* exceptions.
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*
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* The default stack size below is the minimal stack size where a
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* simple recursive function doesn't cause a hard crash.
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*/
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#undef THREAD_STACK_SIZE
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#define THREAD_STACK_SIZE 0x100000
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#endif
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/* for safety, ensure a viable minimum stacksize */
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#define THREAD_STACK_MIN 0x8000 /* 32kB */
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#else /* !_POSIX_THREAD_ATTR_STACKSIZE */

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