Issue #18227: pyexpat now uses a static XML_Memory_Handling_Suite. cElementTree uses the same approach since at least Python 2.6

Modules/posixmodule.c: In function 'posix_sendfile':
Modules/posixmodule.c:7700: warning: ISO C90 forbids mixed declarations and code

Replace malloc() with PyMem_Malloc() when the GIL is held, or with
PyMem_RawMalloc() otherwise.

* Replace malloc() with PyMem_RawMalloc()
* Replace PyMem_Malloc() with PyMem_RawMalloc() where the GIL is not held.
* _Py_char2wchar() now returns a buffer allocated by PyMem_RawMalloc(), instead
  of PyMem_Malloc()

PyMem_Malloc() or PyObject_Malloc().

For example, PyCFunction_Fini() calls PyObject_GC_Del() which calls
PyObject_FREE().

* Add comment explaining the endpoint checks
* Only do the checks in a debug build
* Simplify newblock() to only require a length argument
  and leave the link updates to the calling code.
* Also add comment for the freelisting logic.

This changeset fixes a number of compiler warnings in the Python Launcher
binary for OSX. It also cleans up whitespace usage in those sources.

This changeset fixes a number of compiler warnings in the Python Launcher
binary for OSX. It also cleans up whitespace usage in those sources.

Reformulated the textual change, and applied it to the docstring as well.

Reformulated the textual change, and applied it to the docstring as well.

According to VirtualFree() documentation, the size must be zero if the "free
type" is MEM_RELEASE.

a stack overflow in the marshal module (fix a crash in test_marshal).
Patch written by Jeremy Kloth.

Add new enum:

* PyMemAllocatorDomain

Add new structures:

* PyMemAllocator
* PyObjectArenaAllocator

Add new functions:

* PyMem_RawMalloc(), PyMem_RawRealloc(), PyMem_RawFree()
* PyMem_GetAllocator(), PyMem_SetAllocator()
* PyObject_GetArenaAllocator(), PyObject_SetArenaAllocator()
* PyMem_SetupDebugHooks()

Changes:

* PyMem_Malloc()/PyObject_Realloc() now always call malloc()/realloc(), instead
  of calling PyObject_Malloc()/PyObject_Realloc() in debug mode.
* PyObject_Malloc()/PyObject_Realloc() now falls back to
  PyMem_Malloc()/PyMem_Realloc() for allocations larger than 512 bytes.
* Redesign debug checks on memory block allocators as hooks, instead of using C
  macros

to be consistent with practices in other modules.

Hoist conditional expression out of the loop.
Use rightblock as the guard instead of checking for NULL.

importlib._bootstrap._get_sourcefile().

Thanks to its only use by the C API, it was never properly tested
until now.

Thanks to Neal Norwitz for discovering the bug and Madison May for the patch.

The private attribute was leaking out of importlib and led to at least
one person noticing it. Switch to another hack which won't leak
outside of importlib and is nearly as robust.