Path: utzoo!mnetor!uunet!lll-winken!lll-tis!ames!umd5!cvl!elsie!ado
From: ado@elsie.UUCP (Arthur David Olson)
Newsgroups: comp.sources.d
Subject: Re: Bug found in PD 'localtime'
Message-ID: <8044@elsie.UUCP>
Date: 17 Apr 88 22:07:12 GMT
References: <755@datapg.DataPg.MN.ORG>
Organization: NIH-LEC, Bethesda, MD
Lines: 69
Summary: help wanted

> The PD version of ctime(3) which was recently posted has a problem in
> generating its data files on. . .this AT&T/Convergent 3B1 (System V).
> I have defined USG_COMPAT (and examined the few lines affected in
> localtime.c). . .
>
> My symptom was 'zic' creating small files with zeroes instead of data for
> zones with DST (ie, EST5 OK and EST5EDT bad).
> 
> The problem turned out to be "min_year" and "max_year" were both 2038 A.D.,
> caused by a bug in gmtime(3) where called by setboundaries() in zic.  A note
> in 'timemk.c' says there is a bug in System VR2.0 and BSD4.3 localtime(3),
> so many people might notice it.

Hmmm. . .the bug in System V's gmtime/localtime shouldn't cause problems with
zic, since it uses the public-domain versions of these functions.

If someone out there with a 3B1 could compile the attached program and send me
the results, it might help in tracking down the problem.
-- 
	ado@ncifcrf.gov			ADO is a trademark of Ampex.

#include "stdio.h"

#define TRUE	1
#define FALSE	0

static long		lmin;
static long		lmax;
static int		lsigned;
static unsigned long	ulmin;
static unsigned long	ulmax;
static int		ulsigned;

main()
{
	register long		lbit;
	register unsigned long	ulbit;

	for (lbit = 1; lbit > 0; lbit <<= 1)
		;
	if (lbit == 0) {
		lsigned = FALSE;
		lmin = 0;
		lmax = ~(long) 0;
	} else {
		lsigned = TRUE;
		lmin = lbit;
		lmax = lbit;
		++lmax;
		lmax = -lmax;
	}
	(void) printf("lbit %ld lsigned %d lmin %ld lmax %ld\n",
		lbit, lsigned, lmin, lmax);
	for (ulbit = 1; ulbit > 0; ulbit <<= 1)
		;
	if (ulbit == 0) {
		ulsigned = FALSE;
		ulmin = 0;
		ulmax = ~(unsigned long) 0;
	} else {
		ulsigned = TRUE;
		ulmin = ulbit;
		ulmax = ulbit;
		++ulmax;
		ulmax = -ulmax;
	}
	(void) printf("ulbit %lu ulsigned %d ulmin %lu ulmax %lu\n",
		ulbit, ulsigned, ulmin, ulmax);
	return 0;
}