Call all_type_info_check_for_divergence() also from type_caster_generic::load_impl<>

tests/test_python_multiple_inheritance.py

@@ -30,6 +30,12 @@ class PCD(PC1, PC2):
     pass
 
 
+class PCDI(PC1, PC2):
+    def __init__(self):
+        PC1.__init__(self, 11)
+        PC2.__init__(self, 12)
+
+
 def test_PC():
     d = PC(11)
     assert d.get_base_value() == 11
@@ -69,3 +75,9 @@ def test_PCD():
         match=r"CppDrvd2\.__init__\(\) must be called when overriding __init__$",
     ):
         PCD(11)
+
+
+def test_PCDI():
+    obj = PCDI()
+    with pytest.raises(TypeError, match="^bases include diverging derived types: "):
+        m.pass_CppBase(obj)