Re: How to tell autoconf not to try and run programs

[Ralf Wildenhues]

Hello Christopher,

* Christopher Hulbert wrote on Sun, Apr 06, 2008 at 02:46:21PM CEST:
> If the configure variable cross_compiling=yes, autoconf does not try
> to run compiler-generated programs, at least the one to see if the
> compiler works. Now I don't think I'm technically cross-compiling,

Not so sure.  The compiler certainly has the cross-compilation
characteristic that executables produced with it don't run OOTB.

> but
> I would like a way to tell AC_PROG_CC to not try and run the generated
> executable. The problem is compiling with a compiler that
> automatically links in MPI libraries on HPC's that REQUIRE jobs to be
> submitted through a queue system (in this case LSF). If I manually
> edit my configure script and set cross_compiling=yes, I can build and
> install the package and run the programs through the queue system.

Some systems also provide an automatism to queue such programs into an
interactive queue.  It does work mostly, but it sure gives an entirely
new quality to the statement that configure scripts are slow.  ;-)

> So, is there a cleaner way than setting cross_compiling=yes to get
> that functionality. If not, can I simply set cross_compiling inside a
> test in configure.ac?

See
<http://thread.gmane.org/gmane.comp.sysutils.autoconf.general/10250/focus=10264>
for an answer.  Another, more classic, hackish, way is to use --build
and --host with slightly different but both valid values.  Ugh.

Cheers,
Ralf