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From: ado@elsie.UUCP (Arthur David Olson)
Newsgroups: net.lang.c
Subject: Failure of "long x(cp) char * cp; { return *((long *) cp); }" is a bug?
Message-ID: <6152@elsie.UUCP>
Date: Sat, 28-Jun-86 17:02:03 EDT
Article-I.D.: elsie.6152
Posted: Sat Jun 28 17:02:03 1986
Date-Received: Mon, 30-Jun-86 03:26:59 EDT
Organization: NIH-LEC, Bethesda, MD
Lines: 33

As I understand it, the code produced by some compilers from

	long x(cp)
	char * cp;
	{
		return *((long *) cp);
	}

will cause core dumps if the value of cp isn't "appropriately aligned".
When dealing with such compilers, you get to do something like

	long x(cp)
	char * cp;
	{
		long l;

		function_to_do_arbitrary_copying((char *) &l, cp, sizeof l);
		return l;
	}

to avoid core dumps.

Isn't this really a compiler bug?  Doesn't the cast in the
		return *((long *) cp);
give the compiler all the evidence it needs that it should, *on its own*,
produce code that's the equivalent of the function call?

Does the latest version of X3J11 have anything to say on the matter?
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