+AC_DEFUN([gl_FUNC_FREXPL_NO_LIBM],
+[
+ AC_REQUIRE([gl_MATH_H_DEFAULTS])
+ AC_CACHE_CHECK([whether frexpl() can be used without linking with libm],
+ [gl_cv_func_frexpl_no_libm],
+ [
+ AC_TRY_LINK([#include <math.h>
+ long double x;],
+ [int e; return frexpl (x, &e) > 0;],
+ [gl_cv_func_frexpl_no_libm=yes],
+ [gl_cv_func_frexpl_no_libm=no])
+ ])
+ if test $gl_cv_func_frexpl_no_libm = yes; then
+ gl_FUNC_FREXPL_WORKS
+ case "$gl_cv_func_frexpl_works" in
+ *yes) gl_func_frexpl_no_libm=yes ;;
+ *) gl_func_frexpl_no_libm=no; REPLACE_FREXPL=1 ;;
+ esac
+ else
+ gl_func_frexpl_no_libm=no
+ dnl Set REPLACE_FREXPL here because the system may have frexpl in libm.
+ REPLACE_FREXPL=1
+ fi
+ if test $gl_func_frexpl_no_libm = yes; then
+ AC_DEFINE([HAVE_FREXPL_IN_LIBC], 1,
+ [Define if the frexpl() function is available in libc.])
+ dnl Also check whether it's declared.
+ dnl MacOS X 10.3 has frexpl() in libc but doesn't declare it in <math.h>.
+ AC_CHECK_DECL([frexpl], , [HAVE_DECL_FREXPL=0], [#include <math.h>])
+ else
+ HAVE_DECL_FREXPL=0
+ AC_LIBOBJ([frexpl])
+ fi
+])
+
+dnl Test whether frexpl() works on finite numbers (this fails on
+dnl MacOS X 10.4/PowerPC, on AIX 5.1, and on BeOS) and also on infinite numbers
+dnl (this fails e.g. on IRIX 6.5 and mingw).