Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!purdue!haven!decuac!shlump.nac.dec.com!tkou02.enet.dec.com!diamond
From: diamond@tkou02.enet.dec.com (diamond@tkovoa)
Newsgroups: comp.lang.c
Subject: Re: () ignored in some expressions
Message-ID: <1458@tkou02.enet.dec.com>
Date: 11 Apr 90 01:59:41 GMT
References: <48079@lanl.gov> <1272@sdrc.UUCP>
Reply-To: diamond@tkou02.enet.dec.com (diamond@tkovoa)
Organization: Digital Equipment Corporation Japan , Tokyo
Lines: 17

In article <1272@sdrc.UUCP> scjones@sdrc.UUCP (Larry Jones) writes:

>ANSI C requires that all expressions be evaluated as
>written.  Thus for "a + b + c" the compiler must add a and b
>first, then add c to the result.

No.  For "a + b + c", the compiler may add a + c, then add b to the
result, if it wishes, or if it generates faster code.

This whole discussion concerns whether () may be ignored.  In ANSI,
for "(a + b) + c", the () must be obeyed.  Now the compiler must
add a and b first, then add c, or else do something that has the
same exact behavior.

-- 
Norman Diamond, Nihon DEC     diamond@tkou02.enet.dec.com
This_blank_intentionally_left_underlined________________________________________