| # isnand.m4 serial 12 |
| dnl Copyright (C) 2007-2021 Free Software Foundation, Inc. |
| dnl This file is free software; the Free Software Foundation |
| dnl gives unlimited permission to copy and/or distribute it, |
| dnl with or without modifications, as long as this notice is preserved. |
| |
| dnl Check how to get or define isnand(). |
| |
| AC_DEFUN([gl_FUNC_ISNAND], |
| [ |
| AC_REQUIRE([gl_MATH_H_DEFAULTS]) |
| ISNAND_LIBM= |
| gl_HAVE_ISNAND_NO_LIBM |
| if test $gl_cv_func_isnand_no_libm = no; then |
| gl_HAVE_ISNAND_IN_LIBM |
| if test $gl_cv_func_isnand_in_libm = yes; then |
| ISNAND_LIBM=-lm |
| fi |
| fi |
| dnl The variable gl_func_isnand set here is used by isnan.m4. |
| if test $gl_cv_func_isnand_no_libm = yes \ |
| || test $gl_cv_func_isnand_in_libm = yes; then |
| gl_func_isnand=yes |
| else |
| gl_func_isnand=no |
| HAVE_ISNAND=0 |
| fi |
| AC_SUBST([ISNAND_LIBM]) |
| ]) |
| |
| dnl Check how to get or define isnand() without linking with libm. |
| |
| AC_DEFUN([gl_FUNC_ISNAND_NO_LIBM], |
| [ |
| gl_HAVE_ISNAND_NO_LIBM |
| gl_func_isnand_no_libm=$gl_cv_func_isnand_no_libm |
| if test $gl_cv_func_isnand_no_libm = yes; then |
| AC_DEFINE([HAVE_ISNAND_IN_LIBC], [1], |
| [Define if the isnan(double) function is available in libc.]) |
| fi |
| ]) |
| |
| dnl Prerequisites of replacement isnand definition. It does not need -lm. |
| AC_DEFUN([gl_PREREQ_ISNAND], |
| [ |
| AC_REQUIRE([gl_DOUBLE_EXPONENT_LOCATION]) |
| ]) |
| |
| dnl Test whether isnand() can be used with libm. |
| |
| AC_DEFUN([gl_HAVE_ISNAND_IN_LIBM], |
| [ |
| AC_CACHE_CHECK([whether isnan(double) can be used with libm], |
| [gl_cv_func_isnand_in_libm], |
| [ |
| save_LIBS="$LIBS" |
| LIBS="$LIBS -lm" |
| AC_LINK_IFELSE( |
| [AC_LANG_PROGRAM( |
| [[#include <math.h> |
| #if (__GNUC__ >= 4) || (__clang_major__ >= 4) |
| # undef isnand |
| # define isnand(x) __builtin_isnan ((double)(x)) |
| #elif defined isnan |
| # undef isnand |
| # define isnand(x) isnan ((double)(x)) |
| #endif |
| double x;]], |
| [[return isnand (x);]])], |
| [gl_cv_func_isnand_in_libm=yes], |
| [gl_cv_func_isnand_in_libm=no]) |
| LIBS="$save_LIBS" |
| ]) |
| ]) |
| |
| AC_DEFUN([gl_HAVE_ISNAND_NO_LIBM], |
| [ |
| AC_CACHE_CHECK([whether isnan(double) can be used without linking with libm], |
| [gl_cv_func_isnand_no_libm], |
| [ |
| AC_LINK_IFELSE( |
| [AC_LANG_PROGRAM( |
| [[#include <math.h> |
| #if (__GNUC__ >= 4) || (__clang_major__ >= 4) |
| # undef isnand |
| # define isnand(x) __builtin_isnan ((double)(x)) |
| #else |
| # undef isnand |
| # define isnand(x) isnan ((double)(x)) |
| #endif |
| double x;]], |
| [[return isnand (x);]])], |
| [gl_cv_func_isnand_no_libm=yes], |
| [gl_cv_func_isnand_no_libm=no]) |
| ]) |
| ]) |