Context

in lbc_lnk, kfillmode = jpfillnothing us used to say that nothing should be done to fill halos corresponding to closed boundaries.

Analysis

Using this optional argument, prevent do do the north pole folding because of this test

      ll_IdoNFold = l_IdoNFold .AND. ifill(jpno) /= jpfillnothing

Recommendation

Remove this test!

Context

run.stat, computed in stpctl, is used to check if 2 simulations are identical or not. prtctl is used to identify which tendency term is the first to create a difference between 2 experiments.

Analysis

When the 2 simulations differ, run.stat will show a difference but this difference between the run.stat files may arrive a few time step after the 2 simulations diverge. run.stat is checking the min/max of some values. Using the min/max is convenient as it does not depend on the MPI domain decomposition. However the difference between 2 simulation is usually appearing somewhere between the min/max values and take a few time step to propagate until the min/max values. I would say that this problem is not critical as the first goal of run.stat is to detect a potential difference.

prtctl is using a local sum to avoid this problem. However when the error is very small and the domain on which we apply the sum is large, the error can be hidden by the rounding done on the sum. This is a real critical point as prtctl must find the first term of the equation which diverges

Recommendation

use 2*wp precision in prtctl to make sure that all differences are really detected. Performance is bad but we don't care in this case.

Context

The latest trunk is giving me segmentation violations with WED025 and nn_hls=2. The problem line is setting the heat content in this loop:

         ! Heat content
         DO ji = 1, npti
            jl = jcat(ji)                                                    ! categroy in which new ice is put
            zswinew  (ji) = MAX( 0._wp , SIGN( 1._wp , - za_b(ji,jl) ) )   ! 0 if old ice
         END DO

seemingly because jcat is ill-defined. jcat is set earlier in this loop:

         DO jl = 1, jpl
            DO ji = 1, npti
               IF( zh_newice(ji) > hi_max(jl-1) .AND. zh_newice(ji) <= hi_max(jl) ) THEN
                  a_i_2d(ji,jl) = a_i_2d(ji,jl) + za_newice(ji)
                  v_i_2d(ji,jl) = v_i_2d(ji,jl) + zv_newice(ji)
                  jcat(ji) = jl
               ENDIF
            END DO
         END DO

which doesn't guarantee to set jcat for all npti.

Analysis

Setting jcat=0 before this loop avoids the segmentation fault but risks an out-of-bounds on za_b

Recommendation

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