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From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: comp.lang.c
Subject: Re: Problem with either ANSI 'C' or Dr Dobbs Journal.
Message-ID: <8383@utzoo.UUCP>
Date: Thu, 6-Aug-87 14:21:12 EDT
Article-I.D.: utzoo.8383
Posted: Thu Aug  6 14:21:12 1987
Date-Received: Thu, 6-Aug-87 14:21:12 EDT
References: <449@sugar.UUCP>
Organization: U of Toronto Zoology
Lines: 20

> According to an article on ANSI 'C' in Dr Dobb's Journal, a prototype
> with a fixed number of arguments means the routine may be called without
> unwinding the stack on return... the assumption being that the called
> routine popped its arguments with a "RET N" type instruction.

Sorry, basically wrong.  Unless ANSI has done something terrible since the
draft I've got (1 Oct 1986, the public-comment draft), functions are
required to behave properly, subject to certain restrictions on argument
types, even if a function prototype is visible at definition but not at
call, or vice-versa.  This means, pretty much, that the presence or absence
of a prototype can't make a difference in something as basic as who pops
the stack.

> It then adds that if no prototype is provided, the function may be
> assumed to have a fixed number of arguments.

This is simply wrong:  no prototype means no assumptions.
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