Apply the same versioning to type_info and module_local

Author: dean0x7d

include/pybind11/cast.h

@@ -33,32 +33,6 @@
 
 NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
 NAMESPACE_BEGIN(detail)
-struct value_and_holder;
-
-/// Additional type information which does not fit into the PyTypeObject
-struct type_info {
-    PyTypeObject *type;
-    const std::type_info *cpptype;
-    size_t type_size, holder_size_in_ptrs;
-    void *(*operator_new)(size_t);
-    void (*init_instance)(instance *, const void *);
-    void (*dealloc)(value_and_holder &v_h);
-    std::vector<PyObject *(*)(PyObject *, PyTypeObject *)> implicit_conversions;
-    std::vector<std::pair<const std::type_info *, void *(*)(void *)>> implicit_casts;
-    std::vector<bool (*)(PyObject *, void *&)> *direct_conversions;
-    buffer_info *(*get_buffer)(PyObject *, void *) = nullptr;
-    void *get_buffer_data = nullptr;
-    void *(*module_local_load)(PyObject *, const type_info *) = nullptr;
-    /* A simple type never occurs as a (direct or indirect) parent
-     * of a class that makes use of multiple inheritance */
-    bool simple_type : 1;
-    /* True if there is no multiple inheritance in this type's inheritance tree */
-    bool simple_ancestors : 1;
-    /* for base vs derived holder_type checks */
-    bool default_holder : 1;
-    /* true if this is a type registered with py::module_local */
-    bool module_local : 1;
-};
 
 /// A life support system for temporary objects created by `type_caster::load()`.
 /// Adding a patient will keep it alive up until the enclosing function returns.
@@ -629,7 +603,7 @@ class type_caster_generic {
     /// Try to load with foreign typeinfo, if available. Used when there is no
     /// native typeinfo, or when the native one wasn't able to produce a value.
     PYBIND11_NOINLINE bool try_load_foreign_module_local(handle src) {
-        constexpr auto *local_key = "_pybind11_module_local_typeinfo";
+        constexpr auto *local_key = PYBIND11_MODULE_LOCAL_ID;
         const auto pytype = src.get_type();
         if (!hasattr(pytype, local_key))
             return false;

include/pybind11/detail/internals.h

@@ -84,7 +84,33 @@ struct internals {
 #endif
 };
 
-/// Tracks the `internals` ABI version independent of the main library version
+/// Additional type information which does not fit into the PyTypeObject.
+/// Changes to this struct also require bumping `PYBIND11_INTERNALS_VERSION`.
+struct type_info {
+    PyTypeObject *type;
+    const std::type_info *cpptype;
+    size_t type_size, holder_size_in_ptrs;
+    void *(*operator_new)(size_t);
+    void (*init_instance)(instance *, const void *);
+    void (*dealloc)(value_and_holder &v_h);
+    std::vector<PyObject *(*)(PyObject *, PyTypeObject *)> implicit_conversions;
+    std::vector<std::pair<const std::type_info *, void *(*)(void *)>> implicit_casts;
+    std::vector<bool (*)(PyObject *, void *&)> *direct_conversions;
+    buffer_info *(*get_buffer)(PyObject *, void *) = nullptr;
+    void *get_buffer_data = nullptr;
+    void *(*module_local_load)(PyObject *, const type_info *) = nullptr;
+    /* A simple type never occurs as a (direct or indirect) parent
+     * of a class that makes use of multiple inheritance */
+    bool simple_type : 1;
+    /* True if there is no multiple inheritance in this type's inheritance tree */
+    bool simple_ancestors : 1;
+    /* for base vs derived holder_type checks */
+    bool default_holder : 1;
+    /* true if this is a type registered with py::module_local */
+    bool module_local : 1;
+};
+
+/// Tracks the `internals` and `type_info` ABI version independent of the main library version
 #define PYBIND11_INTERNALS_VERSION 1
 
 #if defined(WITH_THREAD)
@@ -96,6 +122,9 @@ struct internals {
 #define PYBIND11_INTERNALS_ID "__pybind11_internals_v" \
     PYBIND11_TOSTRING(PYBIND11_INTERNALS_VERSION) PYBIND11_INTERNALS_KIND "__"
 
+#define PYBIND11_MODULE_LOCAL_ID "__pybind11_module_local_v" \
+    PYBIND11_TOSTRING(PYBIND11_INTERNALS_VERSION) PYBIND11_INTERNALS_KIND "__"
+
 /// Each module locally stores a pointer to the `internals` data. The data
 /// itself is shared among modules with the same `PYBIND11_INTERNALS_ID`.
 inline internals *&get_internals_ptr() {

include/pybind11/pybind11.h

@@ -870,7 +870,7 @@ class generic_type : public object {
         if (rec.module_local) {
             // Stash the local typeinfo and loader so that external modules can access it.
             tinfo->module_local_load = &type_caster_generic::local_load;
-            setattr(m_ptr, "_pybind11_module_local_typeinfo", capsule(tinfo));
+            setattr(m_ptr, PYBIND11_MODULE_LOCAL_ID, capsule(tinfo));
         }
     }