Use sys.modules.get() in the "with _ModuleLockManager(name):" block
to protect the dictionary key with the module lock and use an atomic
get to prevent race condition.
Remove also _bootstrap._POPULATE since it was unused
(_bootstrap_external now has its own _POPULATE object), add a new
_SENTINEL object instead.
* Rewrite importlib _get_module_lock(): it is now responsible to hold
the imp lock directly.
* _find_and_load() now holds the module lock to check if name is in
sys.modules to prevent a race condition
* bpo-30832: Remove own implementation for thread-local storage
CPython has provided the own implementation for thread-local storage
(TLS) on Python/thread.c, it's used in the case which a platform has
not supplied native TLS. However, currently all supported platforms
(NT and pthreads) have provided native TLS and defined the
Py_HAVE_NATIVE_TLS macro with unconditional in any case.
* bpo-30832: replace NT with Windows
* bpo-30832: change to directive chain
* bpo-30832: remove comemnt which making no sense
- On some versions of FreeBSD, setting the "UTF-8" locale
succeeds, but a subsequent "nl_langinfo(CODESET)" fails
- adding a check for this in the coercion logic means that
coercion will happen on systems where this check succeeds,
and will be skipped otherwise
- that way CPython should automatically adapt to changes in
platform behaviour, rather than needing a new release to
enable coercion at build time
- this also allows UTF-8 to be re-enabled as a coercion
target, restoring the locale coercion behaviour on Mac OS X
`PYTHONFRAMEWORK` is defined in `Makefile` and it shoulnd't be used
in `pyconfig.h`.
`sysconfig.py --generate-posix-vars` reads config vars from Makefile
and `pyconfig.h`. Conflicting variables should be avoided.
Especially, string config variables in Makefile are unquoted, but
in `pyconfig.h` are keep quoted. So it should be private (starts with
underscore).
* Improve signal delivery
Avoid using Py_AddPendingCall from signal handler, to avoid calling signal-unsafe functions.
* Remove unused function
* Improve comments
* Add stress test
* Adapt for --without-threads
* Add second stress test
* Add NEWS blurb
* Address comments @haypo
Based on patch by Victor Stinner.
Add private C API function _PyUnicode_AsUnicode() which is similar to
PyUnicode_AsUnicode(), but checks for null characters.
* bpo-30765: Avoid blocking when PyThread_acquire_lock() is asked not to lock
This is especially important if PyThread_acquire_lock() is called reentrantly
(for example from a signal handler).
* Update 2017-06-26-14-29-50.bpo-30765.Q5iBmf.rst
* Avoid core logic when taking the mutex failed
* bpo-30183: Fixes HP-UX cc compilation error in pytime.c
HP-UX does not support the CLOCK_MONOTONIC identifier, and will fail to
compile:
"Python/pytime.c", line 723: error #2020: identifier
"CLOCK_MONOTONIC" is undefined
const clockid_t clk_id = CLOCK_MONOTONIC;
Add a new section for __hpux that calls 'gethrtime()' instead of
'clock_gettime()'.
* bpo-30183: Removes unnecessary return
- removes PY_WARN_ON_C_LOCALE build time flag
- locale coercion and compatibility warnings are now always compiled
in, but are off by default
- adds PYTHONCOERCECLOCALE=warn runtime option to aid in
debugging potentially locale related compatibility problems
Due to not-yet-resolved test failures on *BSD systems (including
Mac OS X), this also temporarily disables UTF-8 as a locale coercion
target, and skips testing the interpreter's behavior in the POSIX locale.
- new PYTHONCOERCECLOCALE config setting
- coerces legacy C locale to C.UTF-8, C.utf8 or UTF-8 by default
- always uses C.UTF-8 on Android
- uses `surrogateescape` on stdin and stdout in the coercion
target locales
- configure option to disable locale coercion at build time
- configure option to disable C locale warning at build time
The function '_PyArg_ParseStack()' and
'_PyArg_UnpackStack' were failing (with error
"XXX() takes Y argument (Z given)") before
the function '_PyArg_NoStackKeywords()' was called.
Thus, the latter did not raise its more meaningful
error : "XXX() takes no keyword arguments".
'invalid character in identifier' now is raised instead of
'f-string: empty expression not allowed' if a subexpression contains
only whitespaces and they are not accepted by Python parser.
Error messages when pass keyword arguments to some builtins that
don't support keyword arguments contained double parenthesis: "()()".
The regression was introduced by bpo-30534.
Fix a reference in subinterpreters, like test_callbacks_leak() of
test_atexit.
warnoptions is a list used to pass options from the command line to
the sys module constructor. Before this change, the list was shared
by multiple interpreter which is not the expected behaviour. Each
interpreter should have their own independent mutable world.
This change duplicates the list in each interpreter. So each
interpreter owns its own list, so each interpreter can clear its own
list.
* bpo-16500: Allow registering at-fork handlers
* Address Serhiy's comments
* Add doc for new C API
* Add doc for new Python-facing function
* Add NEWS entry + doc nit
* Improves test_underpth_nosite_file to reveal why it fails.
* Enable building with Windows 10 SDK.
* Fix WinSDK detection
* Fix initialization on Windows when a ._pth file exists.
* Fix tabs
* Adds comment about Py_GetPath call.
PEP 432 specifies a number of large changes to interpreter startup code, including exposing a cleaner C-API. The major changes depend on a number of smaller changes. This patch includes all those smaller changes.
If we have a chain of generators/coroutines that are 'yield from'ing
each other, then resuming the stack works like:
- call send() on the outermost generator
- this enters _PyEval_EvalFrameDefault, which re-executes the
YIELD_FROM opcode
- which calls send() on the next generator
- which enters _PyEval_EvalFrameDefault, which re-executes the
YIELD_FROM opcode
- ...etc.
However, every time we enter _PyEval_EvalFrameDefault, the first thing
we do is to check for pending signals, and if there are any then we
run the signal handler. And if it raises an exception, then we
immediately propagate that exception *instead* of starting to execute
bytecode. This means that e.g. a SIGINT at the wrong moment can "break
the chain" – it can be raised in the middle of our yield from chain,
with the bottom part of the stack abandoned for the garbage collector.
The fix is pretty simple: there's already a special case in
_PyEval_EvalFrameEx where it skips running signal handlers if the next
opcode is SETUP_FINALLY. (I don't see how this accomplishes anything
useful, but that's another story.) If we extend this check to also
skip running signal handlers when the next opcode is YIELD_FROM, then
that closes the hole – now the exception can only be raised at the
innermost stack frame.
This shouldn't have any performance implications, because the opcode
check happens inside the "slow path" after we've already determined
that there's a pending signal or something similar for us to process;
the vast majority of the time this isn't true and the new check
doesn't run at all.