Don't return a void value.

Issue #23848: On Windows, faulthandler.enable() now also installs an exception
handler to dump the traceback of all Python threads on any Windows exception,
not only on UNIX signals (SIGSEGV, SIGFPE, SIGABRT).

This function will be reused by faulthandler.

Issue #26588:

* Pass the hash table rather than the key size to hash and compare functions
* _Py_HASHTABLE_READ_KEY() and _Py_HASHTABLE_ENTRY_READ_KEY() macros now expect
  the hash table as the first parameter, rather than the key size
* tracemalloc_get_traces_fill(): use _Py_HASHTABLE_ENTRY_READ_DATA() rather
  than pointer dereference
* Remove the _Py_HASHTABLE_ENTRY_WRITE_PKEY() macro
* Move "PKEY" and "PDATA" macros inside hashtable.c

* Optimize tracemalloc_add_trace(): modify hashtable entry data (trace) if the
  memory block is already tracked, rather than trying to remove the old trace
  and then add a new trace.
* Add _Py_HASHTABLE_ENTRY_WRITE_DATA() macro

* _Py_HASHTABLE_ENTRY_DATA: change type from "char *" to "const void *"
* Add _Py_HASHTABLE_ENTRY_WRITE_PKEY() macro
* Rename _Py_HASHTABLE_ENTRY_WRITE_DATA() macro to
  _Py_HASHTABLE_ENTRY_WRITE_PDATA()
* Add _Py_HASHTABLE_ENTRY_WRITE_DATA() macro

No need to remove the old trace if the memory block didn't move.

The whole test suite takes 6 minutes on my laptop. It takes less than 30
minutes on most buildbots. The TESTTIMEOUT is the timeout for a single test
file.

libregrtest: add a watchdog to run_tests_multiprocess() using
faulthandler.dump_traceback_later().

Issue #26592: _warnings.warn_explicit() now tries to import the warnings module
(Python implementation) if the source parameter is set to be able to log the
traceback where the source was allocated.

Issue #26603:

* Implement finalizer for os.scandir() iterator
* Set the source parameter when emitting the ResourceWarning warning
* Close the iterator before emitting the warning

Issue #26604:

* Add a new optional source parameter to _warnings.warn() and warnings.warn()
* Modify asyncore, asyncio and _pyio modules to set the source parameter when
  logging a ResourceWarning warning

Add parenthesis.

Issue #26588: Enhance assertion in set_reentrant()

Issue #26588: Fix _tracemalloc start/stop: don't play with the reentrant flag.

set_reentrant(1) fails with an assertion error if tracemalloc_init() is called
first in a thread A and tracemalloc_start() is called second in a thread B. The
tracemalloc is imported in a thread A. Importing the module calls
tracemalloc_init(). tracemalloc.start() is called in a thread B.

So it's possible to get debug messages in test_tracemalloc.

Issue #26588.

Try to debug random failure on buildbots.

Timestamps should help to debug slow buildbots, and timeout and hang on
buildbots.

Issue #26530:

* Add C functions _PyTraceMalloc_Track() and _PyTraceMalloc_Untrack() to track
  memory blocks using the tracemalloc module.
* Add _PyTraceMalloc_GetTraceback() to get the traceback of an object.

Issue #26588:

* The _tracemalloc now supports tracing memory allocations of multiple address
  spaces (domains).
* Add domain parameter to tracemalloc_add_trace() and
  tracemalloc_remove_trace().
* tracemalloc_add_trace() now starts by removing the previous trace, if any.
* _tracemalloc._get_traces() now returns a list of (domain, size,
  traceback_frames): the domain is new.
* Add tracemalloc.DomainFilter
* tracemalloc.Filter: add an optional domain parameter to the constructor and a
  domain attribute
* Sublte change: use Py_uintptr_t rather than void* in the traces key.
* Add tracemalloc_config.use_domain, currently hardcoded to 1

Issue #26588: Remove _Py_hashtable_delete() from hashtable.h since the function
is not used. Keep the C code in hashtable.c as commented code if someone needs
it later.

Issue #26588: Remove copy_data, free_data and get_data_size callbacks from
hashtable.h. These callbacks are not used in Python and makes the code more
complex.

Remove also the _Py_HASHTABLE_ENTRY_DATA_AS_VOID_P() macro which uses an unsafe
pointer dereference (can cause memory alignment issue). Replace the macro usage
with _Py_HASHTABLE_ENTRY_READ_DATA() which is implemented with the safe
memcpy() function.

Issue #26588: hashtable.h now supports keys of any size, not only
sizeof(void*). It allows to support key larger than sizeof(void*), but also to
use less memory for key smaller than sizeof(void*).