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Author: byroot

internal/imemo.h

@@ -289,7 +289,8 @@ rb_imemo_class_fields_ptr(VALUE obj_fields)
     }
 
     RUBY_ASSERT(IMEMO_TYPE_P(obj_fields, imemo_class_fields));
-    RUBY_ASSERT(!FL_TEST_RAW(obj_fields, OBJ_FIELD_COMPLEX));
+    // vm_getivar unconditionally ask for a fields ptr.
+    // RUBY_ASSERT(!FL_TEST_RAW(obj_fields, OBJ_FIELD_COMPLEX));
 
     if (RB_UNLIKELY(FL_TEST_RAW(obj_fields, OBJ_FIELD_EXTERNAL))) {
         return IMEMO_OBJ_FIELDS(obj_fields)->as.external.ptr;

variable.c

@@ -1596,8 +1596,8 @@ obj_transition_too_complex(VALUE obj, st_table *table)
         break;
       case T_CLASS:
       case T_MODULE:
-        old_fields = RCLASS_PRIME_FIELDS(obj);
         rb_shape_set_shape_id(obj, shape_id);
+        // FIXME: RCLASS_SET_FIELDS_HASH allocates, if GC trigger `table` might be corrupted.
         RCLASS_SET_FIELDS_HASH(obj, table);
         break;
       default: