Path: utzoo!attcan!uunet!samsung!uakari.primate.wisc.edu!caen!ox.com!ox.com!osm
From: osm@ox.com (Owen Scott Medd)
Newsgroups: comp.unix.ultrix
Subject: Re: Actually it's printf.. (was Re: Another C compiler bug)
Message-ID: <1990Nov13.005753.3382@ox.com>
Date: 13 Nov 90 00:57:53 GMT
References: <22443@dime.cs.umass.edu>
Sender: usenet@ox.com (Usenet News Administrator)
Reply-To: osm@ox.com (Owen Scott Medd)
Organization: OTA Limited Partnership -- Ann Arbor
Lines: 20

In many articles people complain about rounding errors with the Ultrix C
compiler...

> [ ad nauseum... ]

The problem is rounding up when there is a zero in the last displayed
digit.  That is:

	printf("%6.2f\n", .006) prints 0.00,
while	printf("%6.2f\n", .016) prints 0.02

The internal representation is correct, just printf/*cvt are screwed up.

This is a *documented* bug in the Ultrix 4.0 (cc2.0) C compiler (right
there in the release notes) and an undocumented bug in the cc1.31
compiler.  The Atlanta CSC *assures* me that it's fixed in the 4.1 cc,
though they have not followed through on their request (of a week ago!)
of getting me a rush copy of 4.1.

Sigh.