[Patch] Fix configure test for __libc_stack_end

[Matthias Koeppe]

The test for `guile_cv_have_libc_stack_end' does not work reliably
because the compiler can optimize away the use of the variable in the
test program.  This happened to me on Solaris with the Sun Forte C
compiler.

Here is a patch.

--- configure.in.~1.220.~       Mon Jun 16 16:49:24 2003
+++ configure.in        Wed Jun 18 10:49:17 2003
@@ -603,8 +603,9 @@
 
 AC_MSG_CHECKING(for __libc_stack_end)
 AC_CACHE_VAL(guile_cv_have_libc_stack_end,
-[AC_TRY_LINK([extern char *__libc_stack_end;],
-             [char *p = __libc_stack_end;],
+[AC_TRY_LINK([#include <stdio.h>
+extern char *__libc_stack_end;],
+             [printf("%s", (char*) __libc_stack_end);],
              guile_cv_have_libc_stack_end=yes,
              guile_cv_have_libc_stack_end=no)])
 AC_MSG_RESULT($guile_cv_have_libc_stack_end)

-- 
Matthias Koeppe -- http://www.math.uni-magdeburg.de/~mkoeppe