Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!cmcl2!yale!husc6!panda!genrad!decvax!decwrl!pyramid!gould9!ncr-sd!se-sd!curtis
From: curtis@se-sd.UUCP (Curtis Johnson x6241)
Newsgroups: comp.lang.c
Subject: Re: Compiler bug? (return values from functions)
Message-ID: <929@se-sd.UUCP>
Date: Fri, 5-Dec-86 15:58:49 EST
Article-I.D.: se-sd.929
Posted: Fri Dec  5 15:58:49 1986
Date-Received: Sat, 6-Dec-86 21:39:37 EST
References: <898@chalmers.UUCP>
Reply-To: curtis@se-sd.UUCP (Curtis Johnson)
Organization: NCR Corporation, SE - San Diego
Lines: 47


I thought Per might have a version of the compiler that has since been
improved, so I compiled his program (on a Tower XP w/3.00.04), ran it 
and found that 0400 was returned by a().

I looked in K&R for hints and found some ambiguous language describing
the use of the "return" statement.

On page 68 (chapter 4.1), is the statement:

... "Any expression can follow  return:

	return(expression)" ...

There is not a word in this section concerning the usage of parentheses
with the return statment. Hmmmmmm...

On page 203 (Appendix A: C Reference Manual, section 9.10 Return Statement)
I found:

... "A function returns to its caller by means of the  return  statement,
which has one of the forms

	return ;
	return  expression ;" ...

Again, there is no wording concerning the presence ( or absence ) of 
parentheses.

Looking into the definition of "expression" is no help as the only mention
of parentheses with respect to expressions is made concerning primary
expressions only ( which this case is not).

The ANSI draft standard for "C" (July 9, 1986) agrees with K&R to the
extent that parentheses are not explicitly required with the return
statement.

Since K&R and the draft ANSI standard don't mention parentheses with
respect to the return statement, I would guess that implementations that
require parentheses are wrong.


-- 

Curtis Johnson		curtis@se-sd.UUCP
    ...!sdcsvax!ncr-sd!se-sd!curtis
NCR Corp. Systems Engineering, San Diego