Almost all checks are now cached by AC_CACHE_CHECK().
Common patterns are replaced by helper macros.
Variable names now use naming scheme ``ac_cv_func_$funcname``,
``ac_cv_lib_$library_$funcname``, or ``ac_cv_header_$headername_h``.
``SYS_SELECT_WITH_SYS_TIME`` is no longer used.
``uuid_create`` and ``uuid_enc_be`` are provided by libc on BSD. It is
safe to use ``AC_CHECK_FUNCS`` here.
Caching speeds up ./configure -C from ~ 4s to 2.6s on my system.
Co-authored-by: Erlend Egeberg Aasland <erlend.aasland@innova.no>
Freelists for object structs can now be disabled. A new ``configure``
option ``--without-freelists`` can be used to disable all freelists
except empty tuple singleton. Internal Py*_MAXFREELIST macros can now
be defined as 0 without causing compiler warnings and segfaults.
Signed-off-by: Christian Heimes <christian@python.org>
Remove fallbacks for missing round(), copysign() and hypot() in
Python/pymath.c. Python now requires these functions to build.
These fallbacks were needed on Visual Studio 2012 and older. They are
no longer needed since Visual Stuido 2013. Python is now built with
Visual Studio 2017 or newer since Python 3.6.
Building Python now requires a C99 <math.h> header file providing
isinf(), isnan() and isfinite() functions.
Remove the Py_FORCE_DOUBLE() macro. It was used by the
Py_IS_INFINITY() macro.
Changes:
* Remove Py_IS_NAN(), Py_IS_INFINITY() and Py_IS_FINITE()
in PC/pyconfig.h.
* Remove the _Py_force_double() function.
* configure no longer checks if math.h defines isinf(), isnan() and
isfinite().
On Unix, if the sem_clockwait() function is available in the C
library (glibc 2.30 and newer), the threading.Lock.acquire() method
now uses the monotonic clock (time.CLOCK_MONOTONIC) for the timeout,
rather than using the system clock (time.CLOCK_REALTIME), to not be
affected by system clock changes.
configure now checks if the sem_clockwait() function is available.
In Unix operating systems, time.sleep() now uses the clock_nanosleep() function,
if available, which allows to sleep for an interval specified with nanosecond precision.
Co-authored-by: Victor Stinner <vstinner@python.org>
- Remove HAVE_X509_VERIFY_PARAM_SET1_HOST check
- Update hashopenssl to require OpenSSL 1.1.1
- multissltests only OpenSSL > 1.1.0
- ALPN is always supported
- SNI is always supported
- Remove deprecated NPN code. Python wrappers are no-op.
- ECDH is always supported
- Remove OPENSSL_VERSION_1_1 macro
- Remove locking callbacks
- Drop PY_OPENSSL_1_1_API macro
- Drop HAVE_SSL_CTX_CLEAR_OPTIONS macro
- SSL_CTRL_GET_MAX_PROTO_VERSION is always defined now
- security level is always available now
- get_num_tickets is available with TLS 1.3
- X509_V_ERR MISMATCH is always available now
- Always set SSL_MODE_RELEASE_BUFFERS
- X509_V_FLAG_TRUSTED_FIRST is always available
- get_ciphers is always supported
- SSL_CTX_set_keylog_callback is always available
- Update Modules/Setup with static link example
- Mention PEP in whatsnew
- Drop 1.0.2 and 1.1.0 from GHA tests
* Remove m68k-specific hack from ascii_decode
On m68k, alignments of primitives is more relaxed, with 4-byte and
8-byte types only requiring 2-byte alignment, thus using sizeof(size_t)
does not work. Instead, use the portable alternative.
Note that this is a minimal fix that only relaxes the assertion and the
condition for when to use the optimised version remains overly strict.
Such issues will be fixed tree-wide in the next commit.
NB: In C11 we could use _Alignof(size_t) instead, but for compatibility
we use autoconf.
* Optimise string routines for architectures with non-natural alignment
C only requires that sizeof(x) is a multiple of alignof(x), not that the
two are equal. Thus anywhere where we optimise based on alignment we
should be using alignof(x) not sizeof(x).
This is more annoying than it would be in C11 where we could just use
_Alignof(x) (and alignof(x) in C++11), but since we still require only
C99 we must plumb the information all the way from autoconf through the
various typedefs and defines.
In contrast to macOS, libedit is available as its own include file and
library on Linux systems to prevent file name clashes. So if both
libraries are available on the system, readline is currently chosen by
default; and if only libedit is available, it is not found at all. This
patch adds a way to link against libedit by adding the following
arguments to configure:
--with-readline link against libreadline (the default)
--with-readline=editline link against libeditline
--with-readline=no disable building the readline module
--without-readline (same)
The runtime detection of libedit vs. readline was already done in commit
7105319ada (2019-12-04, serge-sans-paille: "bpo-38634: Allow
non-apple build to cope with libedit (GH-16986)").
Fixes: GH-12076 ("bpo-13501 Build or disable readline with Editline")
Fixes: bpo-13501 ("Make libedit support more generic; port readline / libedit to FreeBSD")
Co-authored-by: Enji Cooper (ngie-eign)
Co-authored-by: Martin Panter (vadmium)
Co-authored-by: Robert Marshall (kellinm)
Add pycore_atomic_funcs.h internal header file: similar to
pycore_atomic.h but don't require to declare variables as atomic.
Add _Py_atomic_size_get() and _Py_atomic_size_set() functions.
Co-authored-by: Lawrence D’Anna <lawrence_danna@apple.com>
* Add support for macOS 11 and Apple Silicon (aka arm64)
As a side effect of this work use the system copy of libffi on macOS, and remove the vendored copy
* Support building on recent versions of macOS while deploying to older versions
This allows building installers on macOS 11 while still supporting macOS 10.9.
* bpo-35823: subprocess: Use vfork() instead of fork() on Linux when safe
When used to run a new executable image, fork() is not a good choice
for process creation, especially if the parent has a large working set:
fork() needs to copy page tables, which is slow, and may fail on systems
where overcommit is disabled, despite that the child is not going to
touch most of its address space.
Currently, subprocess is capable of using posix_spawn() instead, which
normally provides much better performance. However, posix_spawn() does not
support many of child setup operations exposed by subprocess.Popen().
Most notably, it's not possible to express `close_fds=True`, which
happens to be the default, via posix_spawn(). As a result, most users
can't benefit from faster process creation, at least not without
changing their code.
However, Linux provides vfork() system call, which creates a new process
without copying the address space of the parent, and which is actually
used by C libraries to efficiently implement posix_spawn(). Due to sharing
of the address space and even the stack with the parent, extreme care
is required to use vfork(). At least the following restrictions must hold:
* No signal handlers must execute in the child process. Otherwise, they
might clobber memory shared with the parent, potentially confusing it.
* Any library function called after vfork() in the child must be
async-signal-safe (as for fork()), but it must also not interact with any
library state in a way that might break due to address space sharing
and/or lack of any preparations performed by libraries on normal fork().
POSIX.1 permits to call only execve() and _exit(), and later revisions
remove vfork() specification entirely. In practice, however, almost all
operations needed by subprocess.Popen() can be safely implemented on
Linux.
* Due to sharing of the stack with the parent, the child must be careful
not to clobber local variables that are alive across vfork() call.
Compilers are normally aware of this and take extra care with vfork()
(and setjmp(), which has a similar problem).
* In case the parent is privileged, special attention must be paid to vfork()
use, because sharing an address space across different privilege domains
is insecure[1].
This patch adds support for using vfork() instead of fork() on Linux
when it's possible to do safely given the above. In particular:
* vfork() is not used if credential switch is requested. The reverse case
(simple subprocess.Popen() but another application thread switches
credentials concurrently) is not possible for pure-Python apps because
subprocess.Popen() and functions like os.setuid() are mutually excluded
via GIL. We might also consider to add a way to opt-out of vfork() (and
posix_spawn() on platforms where it might be implemented via vfork()) in
a future PR.
* vfork() is not used if `preexec_fn != None`.
With this change, subprocess will still use posix_spawn() if possible, but
will fallback to vfork() on Linux in most cases, and, failing that,
to fork().
[1] https://ewontfix.com/7
Co-authored-by: Gregory P. Smith [Google LLC] <gps@google.com>
close_range(2) should be preferred at all times if it's available, otherwise we'll use closefrom(2) if available with a fallback to fdwalk(3) or plain old loop over fd range in order of most efficient to least.
[note that this version does check for ENOSYS, but currently ignores all other errors]
Automerge-Triggered-By: @pablogsal
Add --with-experimental-isolated-subinterpreters build option to
configure: better isolate subinterpreters, experimental build mode.
When used, force the usage of the libc malloc() memory allocator,
since pymalloc relies on the unique global interpreter lock (GIL).
The os.putenv() and os.unsetenv() functions are now always available.
On non-Windows platforms, Python now requires setenv() and unsetenv()
functions to build.
Remove putenv_dict from posixmodule.c: it's not longer needed.
If setenv() C function is available, os.putenv() is now implemented
with setenv() instead of putenv(), so Python doesn't have to handle
the environment variable memory.
Provides a richer platform tag for AIX that we expect to be sufficient for PEP 425
binary distribution identification. Any backports to earlier Python versions will be
handled via setuptools.
Patch by Michael Felt.
Fix stdatomic.h header check for ICC compiler: the ICC implementation
lacks atomic_uintptr_t type which is needed by Python.
Test:
* atomic_int and atomic_uintptr_t types
* atomic_load_explicit() and atomic_store_explicit()
* memory_order_relaxed and memory_order_seq_cst constants
But don't test ATOMIC_VAR_INIT(): it's not used in Python.
