Xref: utzoo comp.unix.microport:546 comp.bugs.sys5:435
Path: utzoo!mnetor!uunet!husc6!mailrus!umix!b-tech!zeeff
From: zeeff@b-tech.UUCP (Jon Zeeff)
Newsgroups: comp.unix.microport,comp.bugs.sys5
Subject: Re: 386/ix bug on doubles inside if-statement ?
Message-ID: <4443@b-tech.UUCP>
Date: 27 Apr 88 21:58:38 GMT
References: <672@altger.UUCP>
Reply-To: zeeff@b-tech.UUCP (Jon Zeeff)
Organization: Branch Technology Ann Arbor, MI
Lines: 25

In article <672@altger.UUCP> dirk@altger.UUCP (dirk) writes:
>Does anyboady have an idea why the following program fails ?
>
>	if (fabs (a) < fabs (b)) printf("a is lower\n"); 

Evidently most of the Sys V '386 compilers produce incorrect code for this.

Often you get:

	fldl	-40(%ebp)
	fcompp

When you should get:

	fcompl	-40(%ebp)

Perhaps the bug is consistent enough that the first form can always be 
replaced by the second form by some add on program.

Does anyone have gcc working well enough that I can throw out this buggy
compiler?

-- 
Jon Zeeff           		Branch Technology,
uunet!umix!b-tech!zeeff  	zeeff%b-tech.uucp@umix.cc.umich.edu