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hello all,<br>
<br>
we've recently discovered an optimizer bug in some<br>
versions of intel fortran 18 which affects the lorenz 96 <br>
model in dart. it's possible the same bug may affect <br>
other dart models as well.<br>
<br>
the lorenz 96 code works correctly with intel fortran<br>
version 17. we've tested the following versions that <br>
we have access to:<br>
<br>
mac os: <br>
18.0.0.104 (August 2017) - has optimizer bug<br>
<br>
linux: <br>
18.0.1.163 (October 2017) - has optimizer bug<br>
<div> 18.0.2.199 (February 2018) - bug fixed<br>
</div>
<div> 18.0.3.222 (April 2018) - bug fixed<br>
</div>
19.0.0.117 (August 2018) - bug fixed<br>
<br>
for our users on cheyenne, the default compiler module<br>
is version 17 so unless you specifically load version 18<br>
you should be fine. unfortunately right now the only available<br>
version of 18 is a bad one.<br>
<br>
if you must run with version 18.0.1 make sure you build <br>
DART with the optimizer flag -O1 (that's dash oh one). <br>
the default -O flag is level 2 and provokes the bug which<br>
results in incorrect answers or possibly a core dump.<br>
<br>
if you have questions, please email dart at ucar.edu and <br>
we'll happily give you more details than you could ever want.<br>
<br>
for those of you in the US, happy thanksgiving. for our<br>
non-US users, NCAR will be closed this thursday and friday.<br>
any email to 'dart' will be answered next monday.<br>
<br>
nancy<br>
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