Check the GIL in PyObject_Malloc()

Issue #26558: The debug hook of PyObject_Malloc() now checks that the GIL is
held when the function is called.

2 files changed, 9 insertions, 3 deletions

diff --git a/Doc/c-api/memory.rst b/Doc/c-api/memory.rst
index fe1cd5f..25867d9 100644
--- a/Doc/c-api/memory.rst
+++ b/Doc/c-api/memory.rst
@@ -341,10 +341,13 @@ Customize Memory Allocators
    Newly allocated memory is filled with the byte ``0xCB``, freed memory is
    filled with the byte ``0xDB``. Additional checks:
 
-   - detect API violations, ex: :c:func:`PyObject_Free` called on a buffer
+   - Detect API violations, ex: :c:func:`PyObject_Free` called on a buffer
      allocated by :c:func:`PyMem_Malloc`
-   - detect write before the start of the buffer (buffer underflow)
-   - detect write after the end of the buffer (buffer overflow)
+   - Detect write before the start of the buffer (buffer underflow)
+   - Detect write after the end of the buffer (buffer overflow)
+   - Check that the :term:`GIL <global interpreter lock>` is held when
+     allocator functions of the :c:data:`PYMEM_DOMAIN_OBJ` domain (ex:
+     :c:func:`PyObject_Malloc`) are called
 
    These hooks are installed by default if Python is compiled in debug
    mode. The :envvar:`PYTHONMALLOC` environment variable can be used to install
diff --git a/Doc/whatsnew/3.6.rst b/Doc/whatsnew/3.6.rst
index 588826b..b644a5c 100644
--- a/Doc/whatsnew/3.6.rst
+++ b/Doc/whatsnew/3.6.rst
@@ -117,6 +117,9 @@ compiled in release mode using ``PYTHONMALLOC=debug``. Effects of debug hooks:
   :c:func:`PyMem_Malloc`.
 * Detect write before the start of the buffer (buffer underflow)
 * Detect write after the end of the buffer (buffer overflow)
+* Check that the :term:`GIL <global interpreter lock>` is held when allocator
+  functions of the :c:data:`PYMEM_DOMAIN_OBJ` domain (ex:
+  :c:func:`PyObject_Malloc`) are called
 
 See the :c:func:`PyMem_SetupDebugHooks` function for debug hooks on Python
 memory allocators.