[Wien] LAPW0 -- again

[Fecher, Gerhard]

Dear all,
I am curious how lapw0 should know in which cycle it is,
there must be a difference between the first and all other cycles,
that means something is not or not completely initialised in the 1st cycle.
There are not too many files to be inspected that are used by lapw0 as input, 
case.clsum contains in the first line the number of the iteration, which is "0." in the first cycle and "1." after the first cycle, and so on .....

However, there is another difference:
after dstart, the third line of case.clmsum is empty 
                TOTAL CHARGE DENSITY GENERATED BY  0. ITERATION 
 Li a_exp            B     6.632941  6.632941  6.632941  781

   ATOMNUMBER =  1
   NUMBER OF LM  5
...

whereas after the first cycle it is, in my simple test case
                TOTAL CHARGE DENSITY GENERATED BY  1. ITERATION 
 Li a_exp            B     6.632941  6.632941  6.632941  781
 LM-max:   5
   ATOMNUMBER =  1
   NUMBER OF LM  5
...

Now, when I insert ' LM-max:   5'  into the empty line of a fresh case.clmsum after dstart, then lapw0 runs without problem altready in the first cycle.
The line with LM-max is also missing after dstart in the case.clmup/dn files of spin polarised cakculations, but there it seems that it doesn't matter .

Solution, if the missing line is the cause for the segmentation faults (maybe through wrong array size by allocation):
1) dstart writes the LM-max line with the correct value into case.clmsum
or
2) lapw0  needs to be inspected in more detail:
lmmax ix used for various allocations, maybe that is the reason why something goes wrong if the empty input line is interpreted wrong
check in lapw0 line 336 ff  (and the format lines)
! READ SCFDATA UNTIL BOTTOM AND INCREASE CYCLENUMBER BY ONE
      if(myid.eq.0) then
         READ(8,2044)  ISCF
         read(8,2043) lmmaxx
      endif
#ifdef Parallel
         call MPI_Bcast(iscf,1,MPI_INTEGER,0,MPI_COMM_WORLD,ierr)
         call MPI_Bcast(lmmaxx,1,MPI_INTEGER,0,MPI_COMM_WORLD,ierr)
#endif
      ISCF=ISCF+1
      if(lmmaxx.eq.0) lmmaxx=ncom
      IF(ISCF.GT.999) ISCF=1
...
(note: ncom=261 from params.inc)

It might also be that trying to read an integer from the empty third line causes also later some other problems with the input, which was not a problem with ifort or gfortran but appears in ifx

(It is not known that the old comments about the OMP problems in lapw0 whether they appeared only in the 1st or also in other cycles,
however from the comments in lapw0.F and the changes file in SRC_lapw0 from 2021, it seems to be not just a problem of ifx)

Ciao
Gerhard

DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy:
"I think the problem, to be quite honest with you,
is that you have never actually known what the question is."

====================================
Dr. Gerhard H. Fecher
Institut of Physics
Johannes Gutenberg - University
55099 Mainz