Path: utzoo!mnetor!uunet!husc6!cmcl2!brl-adm!umd5!purdue!i.cc.purdue.edu!j.cc.purdue.edu!pur-ee!uiucdcs!uxc.cso.uiuc.edu!ccvaxa!aglew
From: aglew@ccvaxa.UUCP
Newsgroups: comp.arch
Subject: Re: RISC data alignment
Message-ID: <28200105@ccvaxa>
Date: 20 Feb 88 21:23:00 GMT
References: <2710@mmintl.UUCP>
Lines: 44
Nf-ID: #R:mmintl.UUCP:2710:ccvaxa:28200105:000:1511
Nf-From: ccvaxa.UUCP!aglew    Feb 20 15:23:00 1988


>Does anyone have any problems with:
>
>foo()
>{
>	struct {
>		double x;
>		int i;
>	} a;
>
>	a.x = 3.1;
>	a.i = 12;
>	printf("%g %d\n",a);
>}
>
>as an example of a legal, portable program (printf isn't necessary,
>any function which takes multiple arguments possibly handed off as a
>struct)? Or does the receiving function have to strictly be declared
>as receiving a like struct? (or is that just "a good idea" vs a true
>restriction in the language?)
>
>	-Barry Shein, Boston University

Well, if this is portable I am really going to be surprised.
Any language lawyers out there with a most recent X3J11?

In my out of date copy, C.3.2.2 says something like "each argument is
evaluated, and each formal parameter is assigned the value of the 
corresponding argument... If the number of arguments or their types
after conversion do not agree with those of the formal parameters, the
behavior is undefined".

Of course, printf is variadic, "...", so type checking doesn't apply.


Andy "Krazy" Glew. Gould CSD-Urbana.    1101 E. University, Urbana, IL 61801   
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