Fixed asserts that could SEGV during shutdown.

During the shutdown sequence, it's possible for the module to have been removed prior to dealloc calls.  Our dealloc calls were accessing the module state, but only for logic assertions.  We can just bail on the assertion if the module state has been destroyed.

This probably never affected OSS, because OSS builds always disable asserts.

PiperOrigin-RevId: 770333761

Author: haberman

python/descriptor_containers.c

@@ -24,6 +24,10 @@ static PyObject* PyUpb_DescriptorMap_Repr(PyObject* _self) {
   return ret;
 }
 
+#define CHECK_TYPE(obj, state_member)                                   \
+  assert(PyUpb_ModuleState_MaybeGet() == NULL || /* During shutdown. */ \
+         Py_TYPE(obj) == PyUpb_ModuleState_Get()->state_member)
+
 // -----------------------------------------------------------------------------
 // ByNameIterator
 // -----------------------------------------------------------------------------
@@ -39,7 +43,7 @@ typedef struct {
 } PyUpb_ByNameIterator;
 
 static PyUpb_ByNameIterator* PyUpb_ByNameIterator_Self(PyObject* obj) {
-  assert(Py_TYPE(obj) == PyUpb_ModuleState_Get()->by_name_iterator_type);
+  CHECK_TYPE(obj, by_name_iterator_type);
   return (PyUpb_ByNameIterator*)obj;
 }
 
@@ -101,7 +105,7 @@ typedef struct {
 } PyUpb_ByNumberIterator;
 
 static PyUpb_ByNumberIterator* PyUpb_ByNumberIterator_Self(PyObject* obj) {
-  assert(Py_TYPE(obj) == PyUpb_ModuleState_Get()->by_number_iterator_type);
+  CHECK_TYPE(obj, by_number_iterator_type);
   return (PyUpb_ByNumberIterator*)obj;
 }
 
@@ -162,7 +166,7 @@ typedef struct {
 } PyUpb_GenericSequence;
 
 PyUpb_GenericSequence* PyUpb_GenericSequence_Self(PyObject* obj) {
-  assert(Py_TYPE(obj) == PyUpb_ModuleState_Get()->generic_sequence_type);
+  CHECK_TYPE(obj, generic_sequence_type);
   return (PyUpb_GenericSequence*)obj;
 }
 
@@ -357,7 +361,7 @@ typedef struct {
 } PyUpb_ByNameMap;
 
 PyUpb_ByNameMap* PyUpb_ByNameMap_Self(PyObject* obj) {
-  assert(Py_TYPE(obj) == PyUpb_ModuleState_Get()->by_name_map_type);
+  CHECK_TYPE(obj, by_name_map_type);
   return (PyUpb_ByNameMap*)obj;
 }
 
@@ -573,7 +577,7 @@ typedef struct {
 } PyUpb_ByNumberMap;
 
 PyUpb_ByNumberMap* PyUpb_ByNumberMap_Self(PyObject* obj) {
-  assert(Py_TYPE(obj) == PyUpb_ModuleState_Get()->by_number_map_type);
+  CHECK_TYPE(obj, by_number_map_type);
   return (PyUpb_ByNumberMap*)obj;
 }