2 # This function determines if the isnan function is available on this
5 AC_DEFUN([AC_FUNC_ISNAN],[
6 AC_SINGLE_CXX_CHECK([HAVE_ISNAN_IN_MATH_H], [ac_cv_func_isnan_in_math_h],
9 int foo(float f) {return isnan(f);}])
10 AC_SINGLE_CXX_CHECK([HAVE_ISNAN_IN_CMATH], [ac_cv_func_isnan_in_cmath],
13 int foo(float f) {return isnan(f);}])
14 AC_SINGLE_CXX_CHECK([HAVE_STD_ISNAN_IN_CMATH], [ac_cv_func_std_isnan_in_cmath],
15 [std::isnan], [<cmath>],
17 using std::isnan; int foo(float f) {return isnan(f);}])