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From: rex@aussie.UUCP (Rex Jaeschke)
Newsgroups: comp.std.c
Subject: Re: compatibility of types
Message-ID: <42.UUL1.3#5077@aussie.UUCP>
Date: 11 Jul 90 21:29:48 GMT
References: <1842@tkou02.enet.dec.com>
Organization: Journal of C Language Translation
Lines: 25

> diamond@tkou02.enet.dec.com (diamond@tkovoa) writes:
> 
> However, you might want to beware of a subtle difference regarding
> some types that you did not ask about.  int(*)[3] and int(*)[5] also
> point to integers, but they are not compatible with each other.
> It's a bit too subtle for me to figure out if each is compatible
> with int* or not.

A pointer to an array of x int is NOT assignment-compatible to a pointer
to an array of y int nor to a pointer to an int.  You MUST use an
explicit cast to compare/copy etc.  them or to mix them when calling a 
function in the presence of such a prototype. It is conceivable that a 
pointer to an array might be a "fat" pointer containing information 
about the underlying array size giving it a different representation 
to a straight int pointer.

Rex

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