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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Error messages
Date: Thu, 16 Jul 2015 18:24:54 -0700
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Richard Heathfield <rjh@cpax.org.uk> writes:
> On 17/07/15 01:36, jacobnavia wrote:
>
> <snip>
>
>> As far as I can see, we can never have two unknown identifiers separated
>> by white space in a legal C program.
>>
>> Is that correct?
>
> I believe so, yes.

This:

    void func(struct foo param);

seems to be legal but useless.  gcc warns:

    c.c:1: warning: 'struct foo' declared inside parameter list
    c.c:1: warning: its scope is only this definition or declaration, which is probably not what you want

As far as I can tell there's no legal way to define or call func.

Since the motivation was to generate a diagnostic, and the above
declaration, even if it's legal (I'm not sure it is) certainly deserves
a diagnostic, I don't think that's a problem.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"