Currently we freeze several modules into the runtime. For each of these modules it is essential to bootstrapping the runtime that they be frozen. Any other stdlib module that we later freeze into the runtime is not essential. We can just as well import from the .py file. This PR lets users explicitly choose which should be used, with the new "-X frozen_modules=[on|off]" CLI flag. The default is "off" for now.
https://bugs.python.org/issue45020
There are a few things I missed in gh-27980. This is a follow-up that will make subsequent PRs cleaner. It includes fixes to tests and tools that reference the frozen modules.
https://bugs.python.org/issue45019
* Constructors of subclasses of some buitin classes (e.g. tuple, list,
frozenset) no longer accept arbitrary keyword arguments.
* Subclass of set can now define a __new__() method with additional
keyword parameters without overriding also __init__().
Release the GIL while performing isatty() system calls on arbitrary
file descriptors. In particular, this affects os.isatty(),
os.device_encoding() and io.TextIOWrapper. By extension,
io.open() in text mode is also affected.
Fix PyAiter_Check to only check for the `__anext__` presense (not for
`__aiter__`). Rename `PyAiter_Check()` to `PyAIter_Check()`,
`PyObject_GetAiter()` -> `PyObject_GetAIter()`.
Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>
The binhex module, deprecated in Python 3.9, is now removed. The
following binascii functions, deprecated in Python 3.9, are now also
removed:
* a2b_hqx(), b2a_hqx();
* rlecode_hqx(), rledecode_hqx().
The binascii.crc_hqx() function remains available.
Fix indentation of <no Python frame> message in a faulthandler
traceback or a Fatal Python error traceback. Example:
Current thread 0x00007f03896fb740 (most recent call first):
Garbage-collecting
<no Python frame>
Frozen modules must be added to several files in order to work properly. Before this change this had to be done manually. Here we add a tool to generate the relevant lines in those files instead. This helps us avoid mistakes and omissions.
https://bugs.python.org/issue45019
Places the locals between the specials and stack. This is the more "natural" layout for a C struct, makes the code simpler and gives a slight speedup (~1%)
Implements a two steps check in `importlib._bootstrap._find_and_load()` to avoid locking when the module has been already imported and it's ready.
---
Using `importlib.__import__()`, after this, does show a big difference:
Before:
```
$ ./python -c 'import timeit; print(timeit.timeit("__import__(\"timeit\")", setup="from importlib import __import__"))'
15.92248619502061
```
After:
```
$ ./python -c 'import timeit; print(timeit.timeit("__import__(\"timeit\")", setup="from importlib import __import__"))'
1.206068897008663
```
---
* Refactor dispatch logic to make flow of control clearer. Moves lltrace and dxprofile instrumentation into DISPATCH macro.
* Remove switch in interpreter loop when using computed gotos. There is no need for two nearly-duplicate dispatch tables.
* Generalize cache names for LOAD_ATTR to allow store and delete specializations.
* Factor out specialization of attribute dictionary access.
* Specialize STORE_ATTR.
Fix the os.set_inheritable() function on FreeBSD 14 for file
descriptor opened with the O_PATH flag: ignore the EBADF error on
ioctl(), fallback on the fcntl() implementation.
The threading debug (PYTHONTHREADDEBUG environment variable) is
deprecated in Python 3.10 and will be removed in Python 3.12. This
feature requires a debug build of Python.