Fix another issue with automatic exception values.

Cython/Compiler/Symtab.py

@@ -2289,6 +2289,8 @@ class CppClassScope(Scope):
             if entry.type.same_as(type):
                 # Fix with_gil vs nogil.
                 entry.type = entry.type.with_with_gil(type.with_gil)
+            elif type.is_cfunction and type.compatible_signature_with(entry.type):
+                entry.type = type
             else:
                 error(pos, "Function signature does not match previous declaration")
         else:

tests/run/cpp_template_subclasses.pyx

@@ -138,3 +138,30 @@ cdef cppclass MyClass[O]:
 cdef cppclass MySubclass[T](MyClass[T]):
     void Invoke(Callback[T]* callback):
       pass
+
+
+cdef cppclass Getter[T]:
+    T get(bint fire) except *:
+        if fire:
+            raise RuntimeError
+        else:
+           raise NotImplementedError
+
+cdef cppclass GetInt(Getter[int]):
+    int get(bint fire) except *:
+        if fire:
+            raise RuntimeError
+        else:
+            return 389
+
+def test_subclass_exception_values(bint fire):
+    """
+    >>> test_subclass_exception_values(False)
+    389
+    >>> test_subclass_exception_values(True)
+    Traceback (most recent call last):
+    ...
+    RuntimeError
+    """
+    cdef GetInt getter
+    return getter.get(fire)