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From: cliff@wesson.phys.ucalgary.ca (Cliff Marcellus)
Newsgroups: comp.sys.mips
Subject: f77 compiler bug (both MIPS and SGI)
Message-ID: <1991Jun17.174155.13484@cpsc.ucalgary.ca>
Date: 17 Jun 91 17:41:55 GMT
Reply-To: cliff@phys.ucalgary.ca
Organization: Institute for Space Research
Lines: 41

I've discovered an interesting 'glitch' in the f77 compiler for
MIPS (and consequently, for SGI, also). given a code skeleton of :

   if (...) goto 10
      .
      .
      .
   do 10 ....
      .
      .
      .
10 continue

From the above, if the 'if' evaluates to TRUE, then the following code,
including the DO loop are supposed to be skipped.  This doesn't happen
under MIPS-fortran.  Instead, the loop-code is executed using a value
of "whatever" for the control loop variable.  Now (personally) I don't
see that as a compiler bug, more a case of antequated coding style.
(ie. the purpose of the '10 continue' becomes ambigous).  Anyway, I thought
I would post this in case others are suffering program failures for the
same or similiar reason.  BTW : the fix to the above is of the form :


    if (...) goto 11
       .
       .
       .
    do 10 ....
       .
       .
       .
 10 continue
 11 continue

ttfn

-- 
Cliff Marcellus                       |  Internet : cliff@phys.ucalgary.ca
Department of Physics and Astronomy   |  SPAN     : CANCAL::CLIFF
The University of Calgary
OPINIONS EXPRESSED WITHIN ARE MY OWN AND NOT THOSE OF THE UNIVERSITY OF CALGARY