Lua: Use atomic writes for pointer fields to match engine behavior

praydog · Mar 8, 2025 · 583192f · 583192f
1 parent 0613741
commit 583192f
Showing 1 changed file with 15 additions and 6 deletions.
diff --git a/src/mods/bindings/Sdk.cpp b/src/mods/bindings/Sdk.cpp
@@ -1014,13 +1014,22 @@ void set_data(void* data, ::sdk::RETypeDefinition* data_type, sol::object& value
                 }
 
                 REManagedObject** field = (REManagedObject**) data;
-                if (field != nullptr && *field != nullptr) {
-                    utility::re_managed_object::release(*field);
-                }
-                if (new_data != nullptr) {
-                    utility::re_managed_object::add_ref(new_data);
+                if (field != nullptr && *field != new_data) {
+                    if (new_data != nullptr) {
+                        utility::re_managed_object::add_ref(new_data);
+                    }
+
+                    // Use a thread-safe atomic exchange. This is what Capcom does for all field assignments.
+                    auto old = *field;
+                    while (_InterlockedCompareExchangePointer((PVOID*)field, new_data, old) != old) {
+                        old = *field;
+                    }
+
+                    if (old != nullptr) {
+                        utility::re_managed_object::release(old);
+                    }
                 }
-                *(REManagedObject**) data = new_data;
+
                 return;
             }
         }