Guard against division by zero in VorticityAuxVars.h

[andrewdnolan]

Adds a check to see if the PseudoThickVertex is zero; if true set NormRelVortVertex and NormPlanetVortVertex to zero (avoiding the previous division by zero).

The issue was exposed using SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF, with the gnu compiler, on chrysalis. The _D modifier in the test name resulted in a debug build, which adds the -ffpe-trap=invalid,zero,overflow flags.

This has not been caught previously, because a standalone Debug build of Omega does not use the -ffpe-trap=invalid,zero,overflow flags.

Closes #556.

Checklist

• Documentation:

  • Design document has been generated and added to the docs
  • User's Guide has been updated
  • Developer's Guide has been updated
  • Documentation has been built locally and changes look as expected

• Linting

  • Pre-commit run locally

• Building

  • CMake build does not produce any new warnings from changes in this PR

• Testing

  aurora, oneapi-ifx, mpich

  • CTests Pass
  • Polaris omega_pr Pass

  chrysalis, oneapi-ifx, openmpi

  • CTests Pass
  • Polaris omega_pr Pass

  frontier, craygnu, mpich

  • CTests Pass
  • Polaris omega_pr Pass

  frontier, craygnu-mphipcc, mpich

  • CTests Pass
  • Polaris omega_pr Pass

  pm-cpu, gnu, mpich

  • CTests Pass
  • Polaris omega_pr Pass

  pm-gpu, gnugpu, mpich

  • CTests Pass
  • Polaris omega_pr Pass

• Provide relevant details in a comment to the PR titled Testing with the following:

  • Which machines CTest unit tests
    have been run on and indicate that are all passing.
  • The Polaris omega_pr test suite
    has passed, using the Polaris e3sm_submodules/Omega baseline
  • Document machine(s), compiler(s), and the build path(s) used for -p for both the baseline (Polaris e3sm_submodules/Omega) and the PR build
  • Indicate "All tests passed" or document failing tests
  • Document testing used to verify the changes including any tests that are added/modified/impacted.

• Performance related PRs: Please include a relevant PACE experiment link documenting performance before and after.

• New tests:

  • CTest unit tests for new features have been added per the approved design.
  • Polaris tests for new features have been added per the approved design (and included in a test suite)

• Stealth Features

  • If any stealth features are included in the PR, please confirm that they have been documented.

[andrewdnolan]

Testing:

A single node, non-threaded, smoke test on chrysalis using debug build:

20260917_140012_rqz30d: 1 test
  SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu (Overall: PASS) details:
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu CREATE_NEWCASE
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu XML
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu SETUP
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu SHAREDLIB_BUILD time=276
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu MODEL_BUILD time=567
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu SUBMIT
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu RUN time=1024
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu MEMLEAK
    PASS SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu SHORT_TERM_ARCHIVER

Prior to this PR, that same test failed with:

29: 
29: Program received signal SIGFPE: Floating-point exception - erroneous arithmetic operation.
29: 
29: Backtrace for this error:
...
17: #0  0x155549b1a62f in ???
22: #0  0x155549b1a62f in ???
42: #0  0x155549b1a62f in ???
52: #0  0x155549b1a62f in ???
25: #0  0x155549b1a62f in ???
30: #0  0x155549b1a62f in ???
28: #0  0x155549b1a62f in ???
41: #0  0x155549b1a62f in ???
17: #1  0xa9e6c1 in _ZZNK5OMEGA16VorticityAuxVars19computeVarsOnVertexERKN6Kokkos4Impl20HostThreadTeamMemberINS1_6SerialEEEiRKNS1_4ViewIPPdJNS1_11LayoutRightENS1_9HostSpaceEEEESF_ENKUliE2_clEi
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/ocn/auxiliaryVars/VorticityAuxVars.h:70
17: #2  0xaa28c0 in _ZN6Kokkos12parallel_forIiZNK5OMEGA16VorticityAuxVars19computeVarsOnVertexERKNS_4Impl20HostThreadTeamMemberINS_6SerialEEEiRKNS_4ViewIPPdJNS_11LayoutRightENS_9HostSpaceEEEESG_EUliE2_S6_EEvRKNS3_31TeamThreadRangeBoundariesStructIT_T1_EERKT0_PPKNSt9enable_ifIXsrNS3_26is_host_thread_team_memberISK_EE5valueEvE4typeE
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/externals/ekat/extern/kokkos/core/src/impl/Kokkos_HostThreadTeam.hpp:788
17: #3  0xaa1352 in _ZN5OMEGA16parallelForInnerIZNKS_16VorticityAuxVars19computeVarsOnVertexERKN6Kokkos4Impl20HostThreadTeamMemberINS2_6SerialEEEiRKNS2_4ViewIPPdJNS2_11LayoutRightENS2_9HostSpaceEEEESG_EUliE2_EEvS8_NS_5RangeEOT_
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/infra/OmegaKokkosHiPar.h:253
17: #4  0xa9f188 in _ZNK5OMEGA16VorticityAuxVars19computeVarsOnVertexERKN6Kokkos4Impl20HostThreadTeamMemberINS1_6SerialEEEiRKNS1_4ViewIPPdJNS1_11LayoutRightENS1_9HostSpaceEEEESF_
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/ocn/auxiliaryVars/VorticityAuxVars.h:68
17: #5  0xa89712 in operator()
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/ocn/AuxiliaryState.cpp:217
17: #6  0xa8f121 in operator()<>
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/infra/OmegaKokkos.h:241
17: #7  0xa8f121 in operator()
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/infra/OmegaKokkosHiPar.h:142
17: #8  0xa971a7 in exec<void>
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/externals/ekat/extern/kokkos/core/src/Serial/Kokkos_Serial_Parallel_Team.hpp:229
17: #9  0xa94870 in execute
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/externals/ekat/extern/kokkos/core/src/Serial/Kokkos_Serial_Parallel_Team.hpp:265
17: #10  0xa918af in parallel_for<Kokkos::TeamPolicy<Kokkos::Serial>, OMEGA::parallelForOuter<1, OMEGA::AuxiliaryState::computeMomAux(const OMEGA::OceanState*, const Array3DReal&, int, int, OMEGA::TimeInterval) const::<lambda(int, const TeamMember&)> >(const string&, const OMEGA::LaunchConfig<1>&, OMEGA::AuxiliaryState::computeMomAux(const OMEGA::OceanState*, const Array3DRea
l&, int, int, OMEGA::TimeInterval) const::<lambda(int, const TeamMember&)>&&)::<lambda(const TeamMember&)> >
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/externals/ekat/extern/kokkos/core/src/Kokkos_Parallel.hpp:146
17: #11  0xa8f307 in parallelForOuter<1, OMEGA::AuxiliaryState::computeMomAux(const OMEGA::OceanState*, const Array3DReal&, int, int, OMEGA::TimeInterval) const::<lambda(int, const TeamMember&)> >
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/infra/OmegaKokkosHiPar.h:139
17: #12  0xa89f3f in _ZNK5OMEGA14AuxiliaryState13computeMomAuxEPKNS_10OceanStateERKN6Kokkos4ViewIPPPdJNS4_11LayoutRightENS4_9HostSpaceEEEEiiNS_12TimeIntervalE
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/ocn/AuxiliaryState.cpp:212
17: #13  0xa8bd74 in _ZNK5OMEGA14AuxiliaryState10computeAllEPKNS_10OceanStateERKN6Kokkos4ViewIPPPdJNS4_11LayoutRightENS4_9HostSpaceEEEEiiNS_12TimeIntervalE
17:     at /gpfs/fs1/home/ac.anolan/repos/Omega/develop/components/omega/src/ocn/AuxiliaryState.cpp:382

Here's a full log file, if you're interested:

/lcrc/group/e3sm/ac.anolan/scratch/chrys/SMS_Vmct_D_P64x1.T62_oQU240.COMEGA-IAF.chrysalis_gnu.20260917_112659_wzv07b/run/e3sm.log.1289521.260917-114035

[andrewdnolan]

Testing

CTest unit tests

• Machine: chrysalis
• Compiler: gnu
• Build type: Debug
• Result: All tests passed
  • Log: /lcrc/group/e3sm/ac.anolan/Omega_PR562/build/feature/ctest_2026-09-17_16:08.log

---

Tried running the omega_pr suite, but hit a filesystem error because chrysalis has run out of inodes. I can run the polaris tests once that's resolved.