From owner-freebsd-hackers@FreeBSD.ORG  Tue Feb 22 14:22:06 2005
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To: Giorgos Keramidas <keramida@ceid.upatras.gr>
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From: des@des.no (=?iso-8859-1?q?Dag-Erling_Sm=F8rgrav?=)
Date: Tue, 22 Feb 2005 15:21:33 +0100
In-Reply-To: <20050221165951.GA2124@gothmog.gr> (Giorgos Keramidas's message
 of "Mon, 21 Feb 2005 18:59:51 +0200")
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cc: freebsd-hackers@freebsd.org
cc: Kathy Quinlan <kat-free@kaqelectronics.dyndns.org>
Subject: Re: Error in my C programming
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Giorgos Keramidas <keramida@ceid.upatras.gr> writes:
> The quotations seem a bit messed up, so I don't know if Peter Jeremy or
> Kathy Quinlan wrote the above paragraph.  Whoever the author was though,
> it may be worth to note that C99 *does* allow single-line comments
> delimited by //.

which leads to the following code being well-formed and well-defined
in both C89 and C99 but having different semantics...

#include <stdio.h>

int
main(void)
{
        int a, b, c;

        a =3D 10;
        b =3D 2;
        c =3D a //* oops! */
            -b;
        switch (c) {
	case 8:
                printf("C99 or C++\n");
		break;
	case -5:
                printf("C89\n");
		break;
	default:
		printf("can't happen\n");
		break;
	}
        return 0;
}

This is actually documented in the C99 rationale.

DES
--=20
Dag-Erling Sm=F8rgrav - des@des.no