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From: "jb at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libfortran/24685] real(16) formatted input is broken for huge values
Date: Thu, 16 Mar 2006 08:30:00 -0000	[thread overview]
Message-ID: <20060316083053.17534.qmail@sourceware.org> (raw)
In-Reply-To: <bug-24685-8500@http.gcc.gnu.org/bugzilla/>



------- Comment #13 from jb at gcc dot gnu dot org  2006-03-16 08:30 -------
(In reply to comment #12)
> The attached C program fails on IA64 because the printf rounds the last digit
> of MIN_LDBL down when it prints it and so it can't be read back in.  The basic
> problem is that LDBL_MAX and LDBL_MIN (or for that matter DBL_MIN and DBL_MAX)
> cannot be represented exactly in decimal form so printf has to do some rounding
> that may make the process non-reversable when trying to go back via strtod or
> strtold. 

Ah, I see. Well, IMHO formatted IO of FOO_MAX/MIN is a rather obscure corner
case, so I think a good enough solution would be to change the testcase to
instead test with FOO_MAX/2 and FOO_MIN*2 (just to check that we have large
enough field widths etc. and not worry about rounding out of range). 

But I'll ask the standards gurus on c.l.f first to make sure.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24685


  parent reply	other threads:[~2006-03-16  8:30 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-11-05 19:34 [Bug libfortran/24685] New: real(10) " jblomqvi at cc dot hut dot fi
2005-11-05 23:24 ` [Bug libfortran/24685] " fxcoudert at gcc dot gnu dot org
2006-02-05 22:20 ` [Bug libfortran/24685] [4.1 only] " fxcoudert at gcc dot gnu dot org
2006-02-05 23:04 ` fxcoudert at gcc dot gnu dot org
2006-02-14 15:48 ` fxcoudert at gcc dot gnu dot org
2006-02-14 15:50 ` fxcoudert at gcc dot gnu dot org
2006-02-16 10:55 ` ebotcazou at gcc dot gnu dot org
2006-02-16 11:12 ` [Bug libfortran/24685] real(16) " fxcoudert at gcc dot gnu dot org
2006-02-16 17:44 ` pinskia at gcc dot gnu dot org
2006-02-23 17:44 ` sje at cup dot hp dot com
2006-03-15  7:29 ` ebotcazou at gcc dot gnu dot org
2006-03-15 16:22 ` jb at gcc dot gnu dot org
2006-03-15 16:44 ` sje at cup dot hp dot com
2006-03-16  8:30 ` jb at gcc dot gnu dot org [this message]
2006-04-01 21:34 ` ebotcazou at gcc dot gnu dot org
2006-04-01 21:35 ` ebotcazou at gcc dot gnu dot org
2006-04-10 12:03 ` jakub at gcc dot gnu dot org
2006-04-21 17:04 ` jakub at gcc dot gnu dot org
2006-04-21 17:22 ` jakub at gcc dot gnu dot org
2006-05-24 18:58 ` fxcoudert at gcc dot gnu dot org
2006-05-24 19:01   ` Andrew Pinski
2006-05-24 19:01 ` pinskia at physics dot uc dot edu
2006-05-24 20:35 ` fxcoudert at gcc dot gnu dot org
2007-05-25 19:50 ` jvdelisle at gcc dot gnu dot org
2007-05-26 17:51 ` dominiq at lps dot ens dot fr
2007-11-03 16:48 ` jvdelisle at gcc dot gnu dot org
2007-11-12  5:44 ` jvdelisle at gcc dot gnu dot org
2008-01-17 11:24 ` [Bug libfortran/24685] real(16) formatted input is broken for huge values (gfortran.dg/default_format_2.f90) burnus at gcc dot gnu dot org
2008-01-17 15:33 ` ebotcazou at gcc dot gnu dot org
2008-01-24 15:09 ` dominiq at lps dot ens dot fr
2008-01-25 15:47 ` dominiq at lps dot ens dot fr
2008-02-23 20:11 ` fxcoudert at gcc dot gnu dot org
2008-02-23 20:11 ` fxcoudert at gcc dot gnu dot org
2008-02-28  7:10 ` uros at gcc dot gnu dot org
2008-12-12 22:20 ` janis at gcc dot gnu dot org
2008-12-12 22:23 ` janis at gcc dot gnu dot org
2008-12-19  1:39 ` howarth at nitro dot med dot uc dot edu
2008-12-19 17:51 ` janis at gcc dot gnu dot org
2008-12-19 18:15 ` janis at gcc dot gnu dot org
2008-12-19 18:23 ` janis at gcc dot gnu dot org

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