run-octave with cygwin

[John W. Eaton]

On 13-Mar-2008, Juhani Saastamoinen wrote:

| 
| Hei,
| 
| On cygwin systems, I've had always problems building
| documentation and doing 'make check', for example,
| 
| $ make check
| make -f octMakefile check
| make[1]: Siirrytään hakemistoon "/home/juhani/octave-hg-release-3-0-x"
| make -C test check
| make[2]: Siirrytään hakemistoon "/home/juhani/octave-hg-release-3-0-x/test"
| ./build_sparse_tests.sh
| ../run-octave --norc --silent --no-history ./fntests.m .
|       4 [main] octave 3156 
| C:\cygwin\home\juhani\octave-hg-release-3-0-x\src\octave.exe: *** fatal 
| error - error while loading shared libraries: 
| /home/juhani/octave-hg-release-3-0-x/src/liboctinterp.dll 
| /home/juhani/octave-hg-release-3-0-x/liboctave/liboctave.dll 
| /home/juhani/octave-hg-release-3-0-x/libcruft/libcruft.dll: cannot open 
| shared object file: No such file or directory
| make[2]: *** [check] Hangup
| 
| Now I looked at the problem more closely and
| found out that the problem is avoided when the shell
| variable LD_PRELOAD isn't defined in run-octave
| (see attached diff). I don't know what systems require
| the definition. Surely some do because it has been put there.
| My linux (Fedora 8) builds are indifferent to it,
| but cygwin build does not accept it.
| Patch proposal for run-octave.in is included,
| but I don't know how to automatically include
| the definition for systems that need it and not
| include it for systems that cannot handle it.

This problem has been discussed several times before.  For example,
here:

  
http://www.nabble.com/Solaris%3A-patches-to-run-octave.in-to14036401.html#a14036600

and here is I think the original discussion:

  http://www.nabble.com/segfault-in-build-of-octave-CVS-to7215281.html#a7226545

I don't think we can unconditionally remove LD_PRELOAD as it is
apparently needed on some systems.  I would consider a patch that
makes it optional in some way, or that only sets it on systems where
it is actually needed, though I'd prefer to have some kind of feature
test rather than just looking at the system type.

jwe