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From: cbp@foster.avid.oz (Cameron Paine)
Newsgroups: comp.std.c
Subject: Evaluation of expressions involving string literals
Summary: What does ("literal" + 2) point to?
Keywords: string literal; expression; pointer arithmetic; broken compiler?
Message-ID: <1990Oct11.064854.12867@foster.avid.oz>
Date: 11 Oct 90 06:48:54 GMT
Organization: Avid Systems Pty Ltd, Melbourne, Australia.
Lines: 34

I'm porting some code to an ANSI-conforming compiler and have encountered
an anomaly which my reading of K&R(2) and H&S(2) hasn't resolved. In the
original code, I used many expressions (the reason for doing this is not
relevant) such as:

	char *cptr;
	cptr = "XYhello, world!" + 2;

which has traditionally rendered:

	*cptr == 'h'		/* because cptr => "hello, world!" */

Under the ANSI-conforming compiler, I find that:

	*cptr == 'X'		/* because cptr => "XYhello, world!" */

Experimentation has revealed that:

	cptr = "XYhello, world!";
	cptr += 2;

achieves the result I'm after but this is of little use to me.

The question then is whether the new compiler's behaviour is correct. The
documentation I have implies that it isn't but I'd like to hear what the
lawyers think.

Thanks.

Cameron
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