From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Wed, 12 Jul 2000 14:16:20 -0700
From: Randolph Fritz <randolph@cyber-dyne.com>
To: 9fans@cse.psu.edu
Subject: [9fans] Silly porting fun
Message-ID: <20000712141620.A1017@cyber-dyne.com>
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So...having cut and ground my teeth on some basics of Plan 9, and
being temporarily unable to download Kenji Arisawa's port of Python, I
decided to try building Python in the APE.  The GNU configure script
provided with Python wouldn't work.  (I am now downloading Arisawa's
port.)

Upon study, I found the source of the difficulty, and I would be
interested in a solution for it, since many widely-available programs
depend on such scripts.  A GNU "configure" script is a shell script
which tests the local system for various features.  It does this, in
part, by compiling many small test programs.  Often the point of the
test programs is a check for the presence of an include file or
symbol, and the main program is trivial.  And therein lies the
problem.

The typical minimal main program from a GNU configure script is:

  main() { return(0); }

The compiler, reasonably enough, decides that this routine never does
anything and is never called, and optimizes it out of existence!  The
linker then cannot find main(), and fails.  Is there an option switch
(preferably) or #pragma I can give to alter this behavior?  Failing
that, would adding "USED(main);" to the program do the trick?

-- 
Randolph Fritz
Eugene, Oregon, USA