f77 -O bug

[Finn Drablos]

I have a fortran program where file names are made in several steps, mainly
in order to create unique file names. The following short test program
shows how it is done.

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      program string
c  Short program to test -O optimization in f77
      character*25 line
      character*10 name
c
      i0 = ichar('0')
      i = 1
      name = 'filename'
      iend = 8
c
      line = 'FILE '//name(1:iend)//'.ext.'//char(i0+i)
      write(*,*) line
      stop
      end


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If I compile this program with f77, the output is 'FILE filename.ext.1'.
However, if I use f77 -O the output is 'FILE filename.ext.', and my
filename is not unique. Of course, the solution is to compile without
the -O option. I don't know if I trust the global optimization
any more ....

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Finn Drablos                 PHONE +47 7 597710        FAX +47 7 597708
MR-Senteret, SINTEF          MHS(EAN)    : finnd at vax.runit.unit.uninett
N-7034 TRONDHEIM, NORWAY     EARN/BITNET : drabloes at norunit
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