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From: chris@trantor.umd.edu (Chris Torek)
Newsgroups: comp.lang.c
Subject: Re: Casting function ptrs
Message-ID: <2763@umd5.umd.edu>
Date: 22 May 88 21:02:48 GMT
References: <281@marob.MASA.COM> <7330003@hpcllz2.HP.COM>
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Reply-To: chris@trantor.umd.edu (Chris Torek)
Organization: University of Maryland, College Park
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In article <7330003@hpcllz2.HP.COM> walter@hpcllz2.HP.COM (Walter Murray)
writes:
>... but I think the following has the virtue of being strictly
>conforming per the dpANS. ...
>
>struct funcs {char *name; void (*func)();};
>char *foo() {return "It worked!";};
>struct funcs f = {"foo",(void(*)())foo};

This is not strictly conforming, because the standard does not say
whether objects of type `void (*)()' are in any way compatible with
objects of type `char *(*)()'.  (It says very little about pointers
to functions, no matter what the return type of the function.  It
does not even say whether `void *' and `t (*)()' are compatible.)
Since, however, `char *' and `void *' are `the same', using a base
type of `void *(*)()' should work.

Most likely, pointers to any function, no matter what the return
type, will have the same format, but it would be nice to have some
guarantees.
-- 
In-Real-Life: Chris Torek, Univ of MD Computer Science, +1 301 454 7163
Domain: chris@mimsy.umd.edu		Path: ...!uunet!mimsy!chris