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From: Thomas Henlich <thenlich@users.sourceforge.net>
To: Janne Blomqvist <blomqvist.janne@gmail.com>
Cc: jerry DeLisle <jvdelisle@charter.net>,
	gfortran <fortran@gcc.gnu.org>,
		gcc patches <gcc-patches@gcc.gnu.org>
Subject: Re: [patch, libgfortran] PR48906 Wrong rounding results with -m32
Date: Sat, 11 Jun 2011 09:13:00 -0000	[thread overview]
Message-ID: <BANLkTikMUeELyUbHnbf_AL49xnfKVzD4qg@mail.gmail.com> (raw)
In-Reply-To: <BANLkTim_o8bM6bJyJxYbKW7y=kJe0fZ2ug@mail.gmail.com>

> I don't agree with this; with the patch we now output 10 significant
> digits, whereas 9 is sufficient for a binary->ascii->binary roundtrip.
> So please retain the "reduce d by one when E editing is used" thing
> for list format and G0. This is just a side effect of using 1PGw.d
> format for list format and G0 in order to avoid duplicating code, but
> we don't need to follow this particular craziness that is due to how
> the scale factor is specified in the standard.

I hadn't noticed this, but I agree with Janne.

It should be easy to implement:

After the switch between F and E editing, we just need to shift the
decimal point and decrement the exponent. No new rounding is required,
because we keep the number of significant digits.

  reply	other threads:[~2011-06-11  7:24 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-03 12:51 [patch, libgfortran] " jerry DeLisle
2011-06-10 17:39 ` [patch, libgfortran] PR48906 " jerry DeLisle
2011-06-11  8:24   ` Janne Blomqvist
2011-06-11  9:13     ` Thomas Henlich [this message]
2011-06-11 14:19       ` jerry DeLisle
2011-06-11 16:05         ` Thomas Henlich
2011-06-14  6:14       ` jerry DeLisle
2011-06-14  8:30         ` Thomas Henlich
2011-06-11 20:01 jvdelisle

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