[Python-checkins] python/dist/src/Modules readline.c,2.59,2.60

[Michael Hudson]

Guido van Rossum <guido@python.org> writes:

>> METH_NOARGS functions are still called with two arguments, one NULL,
>> so put that back into the function definitions (I didn't know this
>> until recently).
>
> Hm, isn't this a bug???

What, that most METH_NOARGS functions are defined

mod_foo(PyObject* self)

or that the call in ceval.c:3211 is

                 x = (*meth)(self, NULL);

?  Tim said in a comment on patch #660559:

   Note that a METH_NOARGS function is still called, at the C 
   level, with two arguments.  The second argument is always 
   NULL, and sooner or later some platform C is going to blow 
   up when that's passed to a function declared to take only 
   one argument ("the usual" cast to PyCFunction shuts up the 
   compile-time warnings).

   It's not your job to fix that everywhere, but new uses of 
   METH_NOARGS shouldn't add to this problem.  Declaring a 
   second PyObject * argument with a name like "unused" 
   or "dummy" would be fine.

As I was mucking about with readline.c anyway, I thought I'd put in
the unused argument and take out the casts.

Cheers,
M.

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