I'm trying to build a case using release-cesm2.1.0-2-g976a1e1, which was modified slightly to run (well) with DART.
(/glade/work/raeder/Models/cesm2_1_relsd_m5.6)
The CIME started as
commit 170db73e00130294bac98fde5dbbcdcde06a33d6 (origin/maint-5.6)
Author: jedwards4b <jedwards@ucar.edu>
Date: Tue Mar 12 05:20:53 2019 +0800
and also has small modifications, which worked fine through 2020-6.
CASEROOT = /glade/work/raeder/Exp/PMO_test0
EXEROOT = /glade/scratch/raeder/PMO_test0/bld
Now case.build fails with with many errors from ESMF in esmf_wrf_timemgr.
My suspicion is that some change in modules or other environment variable is causing ESMF code,
that worked before, to no longer compile. I haven't been able to identify the inconsistency.
The first apparent sign of trouble is
/glade/work/raeder/Exp/PMO_test0/Tools/Makefile:906: recipe for target 'ESMF_ClockMod.o' failed
It looks like the inability to find the compiled ESMF modules leads to most of the errors reported in
/glade/scratch/raeder/PMO_test0/bld/csm_share.bldlog.210507-170428
I searched the CESM Forums, but didn't find anything helpful.
(I tried to look at the Trouble Shooting guide linked from the
linked from the guidelines page,
bb.cgd.ucar.edu
but I got a "file not found" error. Maybe it should be
$ ./manage_externals/checkout_externals --status --verbose
Processing externals description file : Externals.cfg
Processing externals description file : Externals_CLM.cfg
Processing externals description file : Externals_POP.cfg
Processing externals description file : Externals_CISM.cfg
Checking status of externals: clm, fates, ptclm, mosart, ww3, ERROR:root:SVN returned invalid XML message
ERROR: SVN returned invalid XML message
Running checkout_externals with -d does not yield any more information.
(/glade/work/raeder/Models/cesm2_1_relsd_m5.6)
The CIME started as
commit 170db73e00130294bac98fde5dbbcdcde06a33d6 (origin/maint-5.6)
Author: jedwards4b <jedwards@ucar.edu>
Date: Tue Mar 12 05:20:53 2019 +0800
and also has small modifications, which worked fine through 2020-6.
CASEROOT = /glade/work/raeder/Exp/PMO_test0
EXEROOT = /glade/scratch/raeder/PMO_test0/bld
Now case.build fails with with many errors from ESMF in esmf_wrf_timemgr.
My suspicion is that some change in modules or other environment variable is causing ESMF code,
that worked before, to no longer compile. I haven't been able to identify the inconsistency.
The first apparent sign of trouble is
/glade/work/raeder/Exp/PMO_test0/Tools/Makefile:906: recipe for target 'ESMF_ClockMod.o' failed
It looks like the inability to find the compiled ESMF modules leads to most of the errors reported in
/glade/scratch/raeder/PMO_test0/bld/csm_share.bldlog.210507-170428
I searched the CESM Forums, but didn't find anything helpful.
(I tried to look at the Trouble Shooting guide linked from the
linked from the guidelines page,

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$ ./manage_externals/checkout_externals --status --verbose
Processing externals description file : Externals.cfg
Processing externals description file : Externals_CLM.cfg
Processing externals description file : Externals_POP.cfg
Processing externals description file : Externals_CISM.cfg
Checking status of externals: clm, fates, ptclm, mosart, ww3, ERROR:root:SVN returned invalid XML message
ERROR: SVN returned invalid XML message
Running checkout_externals with -d does not yield any more information.