1#
2# This function determines if the isnan function is available on this
3# platform.
4#
5AC_DEFUN([AC_FUNC_ISNAN],[
6AC_SINGLE_CXX_CHECK([ac_cv_func_isnan_in_math_h],   
7                    [isnan], [<math.h>],
8                    [float f; isnan(f);])
9
10if test "$ac_cv_func_isnan_in_math_h" = "yes" ; then
11  AC_DEFINE([HAVE_ISNAN_IN_MATH_H],1,[Set to 1 if the isnan function is found in <math.h>])
12fi
13
14AC_SINGLE_CXX_CHECK([ac_cv_func_isnan_in_cmath],    
15                    [isnan], [<cmath>],
16                    [float f; isnan(f);])
17if test "$ac_cv_func_isnan_in_cmath" = "yes" ; then
18  AC_DEFINE([HAVE_ISNAN_IN_CMATH],1,[Set to 1 if the isnan function is found in <cmath>])
19fi
20
21AC_SINGLE_CXX_CHECK([ac_cv_func_std_isnan_in_cmath],
22                    [std::isnan], [<cmath>],
23                    [float f; std::isnan(f);])
24if test "$ac_cv_func_std_isnan_in_cmath" = "yes" ; then
25  AC_DEFINE([HAVE_STD_ISNAN_IN_CMATH],1,[Set to 1 if the std::isnan function is found in <cmath>])
26fi
27])
28