@@ -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.
@@ -594,6 +594,7 @@ 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);
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	+Fix a crash caused by failing to set :exc:`MemoryError` on allocation failure
	`2`	+when passing :class:`ctypes.Structure` or :class:`ctypes.Union` instances by
	`3`	`+value to ctypes foreign functions.`
Original file line number	Diff line number	Diff line change
`@@ -594,6 +594,7 @@ StructUnionType_paramfunc(ctypes_state st, CDataObject self)`
`594`	`594`	`if ((size_t)self->b_size > sizeof(void*)) {`
`595`	`595`	`ptr = PyMem_Malloc(self->b_size);`
`596`	`596`	`if (ptr == NULL) {`
	`597`	`+ PyErr_NoMemory();`
`597`	`598`	`return NULL;`
`598`	`599`	`}`
`599`	`600`	`memcpy(ptr, self->b_ptr, self->b_size);`