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From: "dir at lanl dot gov" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/32393] gfortran - incorrect run time results
Date: Thu, 21 Jun 2007 12:58:00 -0000	[thread overview]
Message-ID: <20070621125751.17227.qmail@sourceware.org> (raw)
In-Reply-To: <bug-32393-10129@http.gcc.gnu.org/bugzilla/>



------- Comment #14 from dir at lanl dot gov  2007-06-21 12:57 -------
>What is actually the expected result? Depending on the compiler and compiler
>setting, I get completely different results for the second triangular matrix.
>(The first matrix remains always the same.)

What the program does in this section is multiply the diagonal of the matrix by
2 with the line -

      tt=tt+tt

and so (0.8000E+01 -> 0.1600E+02), (0.1000E+02 -> 0.2000E+02) and (0.1300E+02
-> 0.2600E+02 ) and the other three elememts should stay the same. In debug
mode, most compilers will give the correct answer, but the addition is
sometimes being optmized away.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32393


  parent reply	other threads:[~2007-06-21 12:58 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-06-18 14:42 [Bug fortran/32393] New: " dir at lanl dot gov
2007-06-18 14:49 ` [Bug fortran/32393] " dir at lanl dot gov
2007-06-18 14:52 ` dominiq at lps dot ens dot fr
2007-06-18 15:05 ` dir at lanl dot gov
2007-06-18 15:29 ` dominiq at lps dot ens dot fr
2007-06-18 16:16 ` burnus at gcc dot gnu dot org
2007-06-18 18:13 ` dir at lanl dot gov
2007-06-18 18:44 ` dominiq at lps dot ens dot fr
2007-06-18 18:46 ` dominiq at lps dot ens dot fr
2007-06-18 21:04 ` burnus at gcc dot gnu dot org
2007-06-19 12:48 ` dominiq at lps dot ens dot fr
2007-06-20 14:15 ` dir at lanl dot gov
2007-06-20 15:43 ` dominiq at lps dot ens dot fr
2007-06-20 16:21 ` burnus at gcc dot gnu dot org
2007-06-21 12:58 ` dir at lanl dot gov [this message]
2007-06-21 13:23 ` dir at lanl dot gov
2007-06-21 16:16 ` dir at lanl dot gov
2007-06-21 16:29 ` dir at lanl dot gov
2007-06-21 16:48 ` burnus at gcc dot gnu dot org
2007-06-21 17:04 ` dominiq at lps dot ens dot fr
2007-06-21 17:14 ` burnus at gcc dot gnu dot org
2007-06-21 20:06 ` dir at lanl dot gov
2007-06-21 20:11 ` dir at lanl dot gov
2007-06-22  9:41 ` burnus at gcc dot gnu dot org
2007-06-22 13:27 ` burnus at gcc dot gnu dot org
2007-06-22 14:28 ` dir at lanl dot gov
2007-06-22 14:32 ` burnus at gcc dot gnu dot org
2007-06-24 10:51 ` dominiq at lps dot ens dot fr
2007-06-24 11:12   ` Andrew Pinski
2007-06-24 11:13 ` pinskia at gmail dot com
2007-06-24 19:28 ` dominiq at lps dot ens dot fr
2007-06-24 19:37   ` Andrew Pinski
2007-06-24 19:37 ` pinskia at gmail dot com
2007-06-24 19:45 ` burnus at gcc dot gnu dot org
2007-06-24 19:52 ` dominiq at lps dot ens dot fr

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