Path: utzoo!utgpu!watserv1!watmath!att!tut.cis.ohio-state.edu!zaphod.mps.ohio-state.edu!swrinde!mips!troi!tardis!peter
From: peter@dbaccess.com (Peter A. Castro)
Newsgroups: comp.lang.c
Subject: Re: ansi weirdness
Message-ID: <119@tardis.dbaccess.com>
Date: 10 Sep 90 20:08:02 GMT
References: <11305@alice.UUCP>
Organization: DB/Access Inc., Santa Clara, CA
Lines: 32

in article <11305@alice.UUCP>, andrew@alice.UUCP (Andrew Hume) says:
> 
> 
> the following C fragment fails with a strict ANSI compiler (lcc)
> but compiles with sloppy ones (e.g. gcc):
> 
> 	typedef int (*fn)(struct x *);
> 	extern int fn1(struct x *);
> 	extern fn *fp = fn1;
                  ^^^
	don't you mean "extern fn fp = fn1;"  ?
> 
> the ostensible reason is that the two struct x's are different
> (or at least, have different scopes).
> this may be technically correct but is just wrong.
> can anyone explain why anyone would want this batshit behaviour?

  I tried running your example through two ANSI compilers (RS/6000 XLC,
  and Amiga Aztec C 5.0) and on the second extern got a message:
  "Illegal initialization between types POINTER and POINTER."
  However, to me your extern looks like you are making fp a pointer to
  a pointer to a function.  In that case, the compiler is correct in that
  a pointer to a function is not the same as a pointer to a pointer to
  a function.  However, a compiler that is less stringent will let it
  pass because it resolves that pointers are the same base type.
  I guess I have to ask what was your intent.

-- 
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