gfortran compiler fails with missing reference fedisableexcept

gfortran compiler fails with missing reference fedisableexcept

The compilation failure message may be seen when using the gnu compiler, gfortran, on MacOS X when compiling drhook.c.

To compile OpenIFS correctly on a mac requires a small change to the configuration files to add a pre-processor symbol. In addition, please be aware that the FCM command will hang if more than one thread is being used (see below).

For the required compiler/build option, make a copy of the configuration. e.g. assuming the use of the GNU compilers:

cd cfg
cp gnu-opt.cfg mac-opt.cfg

Edit mac_gnu-opt.cfg and find the line which defines the pre-processor symbols for the C compiler (gcc):

$OIFS_CCDEFS{?} = BLAS LITTLE LINUX INTEGER_IS_INT _ABI64

add 'DARWIN' to this line:

$OIFS_CCDEFS{?} = BLAS LITTLE LINUX INTEGER_IS_INT _ABI64 DARWIN

and save the file.

To compile OpenIFS with this new configuration file set:

export OIFS_COMP=mac
export OIFS_BUILD=opt

which tells the build system to use the file: mac-opt.cfg. The same change can be made to the un-optimized compilation configuration: gnu-noopt.cfg.


FCM hangs if more than one thread is used

There is a known issue where more than one thread causes the fcm command to hang. Until this is fixed only use 1 thread for compilation e.g.

fcm make -j1

This will unfortunately result in longer compile times.

<script type="text/javascript" src="https://software.ecmwf.int/issues/s/en_UKet2vtj/787/12/1.2.5/_/download/batch/com.atlassian.jira.collector.plugin.jira-issue-collector-plugin:issuecollector/com.atlassian.jira.collector.plugin.jira-issue-collector-plugin:issuecollector.js?collectorId=5fd84ec6"></script>