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From: "dominiq at lps dot ens.fr" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/60128] [4.8/4.9 Regression] Wrong ouput using en edit descriptor
Date: Sun, 16 Feb 2014 20:49:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60128

--- Comment #5 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
While the patch in comment 4 fixed they PR, it was quite hawkish and did not
explained the problem. After a deeper analysis it turns out that it is yet
another "off by one bug" fixed by the following one liner:

--- ../_clean/libgfortran/io/write_float.def    2014-01-21 08:30:57.000000000
+0100
+++ libgfortran/io/write_float.def    2014-02-16 20:56:56.000000000 +0100
@@ -1204,7 +1200,7 @@ determine_en_precision (st_parameter_dt 
   if (nprinted == -1)
     return -1;

-  int e = atoi (&buffer[5]);
+  int e = atoi (&buffer[4]);
   int nbefore; /* digits before decimal point - 1.  */
   if (e >= 0)
     nbefore = e % 3;

as &buffer[5] does not include the sign of the exponent.