incrementing after a cast

[der Mouse]

In article <2319 at mtgzz.UUCP>, bds at mtgzz.UUCP writes:
> In article <349 at apple.UUCP>, kanner at apple.UUCP (Herbert Kanner) writes:
>> 		L = *((sometype *) chp)++;
>> Our problem arises with the allegation that K&R makes this construct
>> illegal.
> By parenthesising the expression:
> 	L = (*((sometype *) chp))++
> Then [it's legal].
> Happily, it is the one you want.

I certainly hope not.  The intent was clearly to increment chp by
sizeof(sometype), or something very much like that.  Your proposed
parse results in an expression that doesn't touch chp; even *it* won't
be legal unless "sometype" can have ++ applied to it - for it's
something of type "sometype" that it's ++ing.

You also mention (I deleted it) that this parse is generated even
without the parentheses.  Well, I don't know what compiler you're
using.  Here is what my machine (VAX750/MtXinu4.3+NFS) gives:

	% cat x.c
	main()
	{
	 int i;
	 int j;
	 char *cp;
	
	 cp = (char *) &i;
	 j = *((int *)cp)++;
	}
	% cc x.c
	"x.c", line 8: illegal lhs of assignment operator
	%

					der Mouse

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