Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!ira.uka.de!fauern!opal!mailgzrz!w414zrz!jaenicke
From: jaenicke@w414zrz.zrz.tu-berlin.de (Lutz Jaenicke)
Newsgroups: comp.sys.apollo
Subject: Re: Problems with Fortran-Compiler
Message-ID: <262@mailgzrz.tu-berlin.de>
Date: 27 Feb 91 13:20:39 GMT
References: <250@mailgzrz.tu-berlin.de> <4ff9d7df.3593b@digital.sps.mot.com> <HANCHE.91Feb24143249@hufsa.imf.unit.no>
Sender: news@mailgzrz.tu-berlin.de
Organization: TUBerlin
Lines: 64
Nntp-Posting-Host: w414zrz.ee.tu-berlin.de

In article <HANCHE.91Feb24143249@hufsa.imf.unit.no> hanche@imf.unit.no (Harald Hanche-Olsen) writes:
>In article <4ff9d7df.3593b@digital.sps.mot.com> chen@digital.sps.mot.com (Jinfu Chen) writes:
>
>   In article <250@mailgzrz.tu-berlin.de> jaenicke@w414zrz.zrz.tu-berlin.de (Lutz Jaenicke) writes:
>   > [ Description of large FORTRAN arrays filling up the executable ]
>
>   I noticed similar situation with cc6.7. It turns out when a large size of
>   static variable is declared (large array), the executable is filled. Then I
>   found out a compiler switch -compress in /com/cc (-W0,-compress in /bin/cc)
>   which works quite well.
>
>   Checking over ftn.hlp and man f77 I couldn't find similar switch. Maybe
>   someone knows FORTRAN could help?
>
>One common way to deal with large arrays in FORTRAN is the following:
>Make your FORTRAN main program a subroutine, then write a tiny C
>routine main() that allocates the array using malloc() and then passes
>the resulting pointer to the FORTRAN program.  This has the added
>advantage that you could specify the amount of storage on the command
>line.
>

During the last days i tried several combinations of compiler and
linker switches and i found some strange way to reduce the size
of the executable files. Since the LOCAL variables are allocated 
on the stack, i declared my PROGRAM blocks to be subroutines and
wrote a new PROGRAM block which is just one line with a call.
The variables are declared in the SUBROUTINE and like "abracadabra"
the filesize is minimized:

Normal CODE:			NEW CODE:

program test			program test1
real (large_number),...		call test()
...				end
			  c
				subroutine test()
				real (large_number),...
				...

The Compiler does argue about an exceeded stack_size, but 
declaring a larger stack using "-A stacksize,hexnum" ld-switch
ore just linking as before doesn't make any difference. The
program is running well (but may be i'm naive and the
program crash will occure some minutes after i posted this 
information).

BTW, i found another problem with the fortran compiler:
When i do use the "#include"-Statement and use the sourcefile with
.F extension, preprocessing is performed well, but
the ftn-compiler will not process the file, because some 
lines "#..." are left. I have to trick ftn by -W0,-inline,#
(is Ok, because it was easy to rewrite the sources, so there is
no other "#"-sign left). Under SR10.2 there were none of these
problems at all.

Since "ld" is new (Jul 2 1990 ld) and "f77" is new (Jul 27 1990 f77),
the question is left, if the above mentioned points are
new FEATURES ore if there is a new compiler version,
which we will need soon.

Lutz Jaenicke, TU-Berlin, Institut fuer Elektrische Maschinen
jaenicke@w414zrz.ee.tu-berlin.de
                ----