Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!snorkelwacker!bloom-beacon!news
From: tuna@athena.mit.edu (Kirk 'UhOh' Johnson)
Newsgroups: comp.lang.c
Subject: function declarator strangeness
Summary: yep, i read K&R and the FAQ posting, but they didn't help
Message-ID: <1990May30.173922.11825@athena.mit.edu>
Date: 30 May 90 17:39:22 GMT
Sender: news@athena.mit.edu (News system)
Organization: Massachusetts Institute of Technology
Lines: 60


the following bits of grammar are culled from appendix A of K&R (1st
ed.):

    function-declarator:                          /* page 204 */
        declarator ( parameter-list_opt )

    declarator:                                   /* page 194 */
        identifier
        ( declarator )
        * declarator
        declarator ( )
        declarator [ constant-expression_opt ]

so a function "foo" returning a pointer to a function returning an int
would be declared as:

    int (*foo())()
    {
      /* body of foo */
    }

imagine that i'd like "foo" to take one argument, arg, an integer.
given the bits of grammar shown above, i would expect use:

    int (*foo())(arg)
        int arg;
    {
      /* body of foo */
    }

unfortunately, both pcc and gcc choke upon such a declaration. but if
i rearrange things as

    int (*foo(arg))()
        int arg;
    {
      /* body of foo */
    }

both compilers generate code which seems to do the right thing,
despite the fact that this declaration of "foo" doesn't seem to match
the grammar shown in my copy of K&R (1st ed.).

anybody have any helpful comments? how should the function-declarator
grammar really read? if the problem is that K&R (1st ed.) is out of
date, is there a better reference that isn't?

although i will try to keep up with comp.lang.c to look for responses
to my questions, i'd appreciate it if responses could also be e-mailed
so i don't inadvertently miss them.

thanks in advance for any help

kirk
--

-------------------------------------------------------------------------------
kirk johnson                                                    `Eat blue dogs
tuna@masala.lcs.mit.edu                                          and dig life.'