Detect Cross Compiler

[Too, Justin A.]

Hi,
As a whole, my project is not being cross-compiled, but there is a test that 
uses a user-specified compiler on some test code and then runs the generated 
executable. The problem is that the user may specify to cross-compile this test 
code, in which case the executable should NOT be run. Therefore, I would like 
to set an AM_CONDITIONAL(IS_USING_CROSS_COMPILER), for example.

Say the user specifies the test compiler on the configure line using

—with-test-compiler=<compiler>.

What I would like to do is have configure detect that this compiler, 
$with_test_compiler, is a cross-compiler for the host system and then I can set 
my AM_CONDITIONAL to use in my Makefile.am's. I'm aware of AC_RUN_IFELSE and 
AC_LANG_PROGRAM, but I don't see a way to feed these macros a different 
compiler. AC_LANG and AC_LANG_PUSH don't seem to be useful in this scenario 
either.

Any tips?

Thanks,
Justin