Harden fix

Author: erlend-aasland

Tools/clinic/clinic.py

@@ -4710,9 +4710,13 @@ def bad_node(self, node):
 
         p = Parameter(parameter_name, kind, function=self.function, converter=converter, default=value, group=self.group)
 
-        if (c_name or parameter_name) in self.function.parameters:
+        names = [k.name for k in self.function.parameters.values()]
+        key = f"{parameter_name}_{c_name}" if c_name else parameter_name
+        if parameter_name in names[1:]:
             fail("You can't have two parameters named " + repr(parameter_name) + "!")
-        self.function.parameters[c_name or parameter_name] = p
+        elif names and parameter_name == names[0] and c_name is None:
+            fail("Params named 'module' or 'self' need custom C names")
+        self.function.parameters[key] = p
 
     def parse_converter(self, annotation):
         if (hasattr(ast, 'Constant') and