From: stevens <lipengyu@kylinos.cn>
Date: Tue, 14 Jul 2026 16:48:17 +0000 (+0800)
Subject: gh-151126: Fix `PyErr_NoMemory`  errors in `_ctypes.c`  (#152720)
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d807210fee5606f8d504c1677f7e5ecb5f208a1e;p=thirdparty%2FPython%2Fcpython.git

gh-151126: Fix `PyErr_NoMemory`  errors in `_ctypes.c`  (#152720)
---

diff --git a/Misc/NEWS.d/next/Library/2026-07-01-11-29-13.gh-issue-151126.eElGy5.rst b/Misc/NEWS.d/next/Library/2026-07-01-11-29-13.gh-issue-151126.eElGy5.rst
new file mode 100644
index 000000000000..d5ec1d254ef0
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-07-01-11-29-13.gh-issue-151126.eElGy5.rst
@@ -0,0 +1,3 @@
+Fix a crash caused by failing to set :exc:`MemoryError` on allocation failure
+when passing :class:`ctypes.Structure` or :class:`ctypes.Union` instances by
+value to ctypes foreign functions.
diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
index e891249668c2..adfdf44e5360 100644
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -673,6 +673,7 @@ StructUnionType_paramfunc(ctypes_state *st, CDataObject *self)
     if ((size_t)self->b_size > sizeof(void*)) {
         ptr = PyMem_Malloc(self->b_size);
         if (ptr == NULL) {
+            PyErr_NoMemory();
             return NULL;
         }
         memcpy(ptr, self->b_ptr, self->b_size);