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From: shap@bunker.UUCP (Joseph D. Shapiro)
Newsgroups: comp.sys.ibm.pc.programmer
Subject: Re: No Aliasing Compile Option
Keywords: Microsoft 6.0 C update woes
Message-ID: <12215@bunker.UUCP>
Date: 4 Jun 90 21:22:12 GMT
References: <1990May23.234917.21858@uunet!unhd> <250@demott.COM>
Reply-To: shap@clunker.UUCP (Joseph D. Shapiro)
Organization: ISC-Bunker Ramo, an Olivetti Company, Shelton, Ct
Lines: 40

In article <250@demott.COM> kdq@demott.COM (Kevin D. Quitt) writes:
>    Unless I'm greatly mistaken, the only problem for optimization with
>aliasing involves the use of a variable and its alias *within the same
>function*.  Calling a function with a pointer doesn't hurt, since the
>compiler can know that variables may not be preserved across the
>function call.  I've used the aliasing release on programs that follow
>this model with nary a problem.

how about the following....

In file a.c

	static int foo;

	main()
	{
		bar(foo);
	}

	baz()
	{
		foo++;
	}

in file b.c

	foo(int x)
	{
		... establish a value for x here ...
		baz();
		... reference x here ...
	}

is this not aliasing as well?
will not -Oa cause trouble in b.c?
-- 
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Joe Shapiro					"My other car is a turbo...
ISC-Bunker Ramo     				 ...too."
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