FIX: Code Generation with Concatenation & LEN_TRIM

The information in this article applies to:

• Microsoft FORTRAN for MS-DOS, versions 5.0 and 5.1
• Microsoft FORTRAN for OS/2, versions 5.0 and 5.1

SYMPTOMS

When the code below is compiled with /Od, incorrect code is genererated for the second assignment statement for 'lmessage'.

RESOLUTION

To work around the problem, either

1. Do not use /Od (this will enable optimization.

   -or-

2. Remove the LEN_TRIM function imbedded in the 'lmessage' statement and replace it with a temporary variable set equal to LEN_TRIM(ltask).

STATUS

Microsoft has confirmed this to be a bug in the products listed above. This problem was corrected in FORTRAN PowerStation, version 1.0.

MORE INFORMATION

The following sample code can be used to demonstrate the problem.

Sample code

      implicit none

      integer pmsgidsz
      parameter (pmsgidsz=2)
      character pmsgk*(pmsgidsz)
      parameter (pmsgk='k')

      character mcosrcmd*1, mcosrctk*1, mcomsgst*300,
     1          mcomsgnum*2, mcouppgwstate(10)*1, mcoprcnam*16

      common /mco/ mcosrcmd, mcosrctk, mcomsgst, mcomsgnum,
     1          mcouppgwstate, mcoprcnam

      integer lvar
      character lcmm*1
      character lampid*1, ltask*80, lwindid*1
      character lmessage*301, luserid*2, lappmsgid*(pmsgidsz)

      mcomsgst = 'abcopy1.flb;1,c,cd,ie'
      lampid = mcomsgst(2:2)
      lcmm = 'b'
      mcoprcnam = 'ada'
      mcomsgnum = '01'
      mcosrcmd = 'c'
      mcosrctk = 'c'
      mcouppgwstate(1) = '1'

      lvar = 3
      do while (mcomsgst(lvar:lvar) .ne. ',')
        lvar = lvar+1
      end do

      ltask = mcomsgst(3:lvar+1)

      lwindid = mcomsgst(lvar+1:lvar+1)
      luserid = mcomsgst(lvar+3:lvar+4)
      lappmsgid = mcomsgst(lvar+6:lvar+6+pmsgidsz-1)

      lmessage = lcmm//' '//mcoprcnam(1:2)//mcomsgnum//
     1           pmsgk//ltask(1:len_trim(ltask))//
     2            ','//lwindid//','//luserid//','//lappmsgid//
     3           mcosrcmd//mcosrctk//lampid//','//mcouppgwstate(1)

      write(*,*) lmessage

      lmessage = lcmm//' '//mcoprcnam(1:2)//mcomsgnum//
     1           pmsgk//ltask(1:len_trim(ltask))//
     2            ','//lwindid//','//luserid//','//lappmsgid//
     3           mcosrcmd//mcosrctk//lampid//','//mcouppgwstate(1)

      write(*,*) lmessage

      end