The startup refactoring means command line settings
are now applied after settings are read from the
environment.
This updates the way command line settings are applied
to account for that, ensures more settings are first read
from the environment in _PyInitializeCore, and adds a
simple test case covering the flags that are easy to check.
Fix the pthread+semaphore implementation of
PyThread_acquire_lock_timed() when called with timeout > 0 and
intr_flag=0: recompute the timeout if sem_timedwait() is interrupted
by a signal (EINTR).
See also the PEP 475.
The pthread implementation of PyThread_acquire_lock() now fails with
a fatal error if the timeout is larger than PY_TIMEOUT_MAX, as done
in the Windows implementation.
The check prevents any risk of overflow in PyThread_acquire_lock().
Add also PY_DWORD_MAX constant.
Rework the code choosing BLAKE2 code paths from using the optimized
variant on all x86_64 machines to using it when SSSE3 or better
supported instructions sets are available.
Firstly, this solves the problem of using pure SSE2 code path on x86_64
machines. As reported in the bug, this code is slower than the reference
code on all tested x86_64 machines. Furthermore, on Athlon64 that lacks
SSSE3, it is even 2.5 times slower than the reference code! Checking
for SSSE3 therefore ensures that the optimized implementation will only
be used when it has a chance of performing better.
Secondly, this makes it possible to use SSSE3+ optimizations on 32-bit
x86 systems. This allows for even 2 times speed gain on modern 32-bit
x86 systems (tested in a 32-bit chroot).
Fix the following Coverity warning:
>>> CID 1420038: Control flow issues (DEADCODE)
>>> Execution cannot reach this statement: "res = sem_trywait(self->han...".
321 res = sem_trywait(self->handle);
The deadcode was introduced by the commit
c872d39d32.
Fix timeout rounding in time.sleep(), threading.Lock.acquire() and
socket.socket.settimeout() to round correctly negative timeouts between -1.0 and
0.0. The functions now block waiting for events as expected. Previously, the
call was incorrectly non-blocking.
bpo-31803: time.clock() and time.get_clock_info('clock') now emit a
DeprecationWarning warning.
Replace time.clock() with time.perf_counter() in tests and demos.
Remove also hasattr(time, 'monotonic') in test_time since time.monotonic()
is now always available since Python 3.5.
Always pass -1, or INFTIM where defined, to the poll() system call when
a negative timeout is passed to the poll.poll([timeout]) method in the
select module. Various OSes throw an error with arbitrary negative
values.
Freeze all the objects tracked by gc - move them to a permanent generation
and ignore all the future collections. This can be used before a POSIX
fork() call to make the gc copy-on-write friendly or to speed up collection.
* Rewrite win_perf_counter() to only use integers internally.
* Add _PyTime_MulDiv() which compute "ticks * mul / div"
in two parts (int part and remaining) to prevent integer overflow.
* Clock frequency is checked at initialization for integer overflow.
* Enhance also pymonotonic() to reduce the precision loss on macOS
(mach_absolute_time() clock).
time.clock() and time.perf_counter() now use again C double
internally.
Remove also _PyTime_GetWinPerfCounterWithInfo(): use
_PyTime_GetPerfCounterDoubleWithInfo() instead on Windows.
* Separated functions and constants descriptions in sections.
* Added a note about the limitations of timezone constants.
* Removed redundant lists from the module docstring.
See PEP 539 for details.
Highlights of changes:
- Add Thread Specific Storage (TSS) API
- Document the Thread Local Storage (TLS) API as deprecated
- Update code that used TLS API to use TSS API
While a rare potential failure (it requires swapping out zlib.decompress() itself and forcing it to return a non-bytes object), this change prevents a potential C-level assertion failure and instead substitutes it with an exception.
Thanks to Oren Milman for the patch.
Python requires C implementations provide memmove, so we shouldn't need to check for it. The only place using this configure check was expat, where we can simply always define HAVE_MEMMOVE.