| 1 | # isnand.m4 serial 11 |
| 2 | dnl Copyright (C) 2007-2014 Free Software Foundation, Inc. |
| 3 | dnl This file is free software; the Free Software Foundation |
| 4 | dnl gives unlimited permission to copy and/or distribute it, |
| 5 | dnl with or without modifications, as long as this notice is preserved. |
| 6 | |
| 7 | dnl Check how to get or define isnand(). |
| 8 | |
| 9 | AC_DEFUN([gl_FUNC_ISNAND], |
| 10 | [ |
| 11 | AC_REQUIRE([gl_MATH_H_DEFAULTS]) |
| 12 | ISNAND_LIBM= |
| 13 | gl_HAVE_ISNAND_NO_LIBM |
| 14 | if test $gl_cv_func_isnand_no_libm = no; then |
| 15 | gl_HAVE_ISNAND_IN_LIBM |
| 16 | if test $gl_cv_func_isnand_in_libm = yes; then |
| 17 | ISNAND_LIBM=-lm |
| 18 | fi |
| 19 | fi |
| 20 | dnl The variable gl_func_isnand set here is used by isnan.m4. |
| 21 | if test $gl_cv_func_isnand_no_libm = yes \ |
| 22 | || test $gl_cv_func_isnand_in_libm = yes; then |
| 23 | gl_func_isnand=yes |
| 24 | else |
| 25 | gl_func_isnand=no |
| 26 | HAVE_ISNAND=0 |
| 27 | fi |
| 28 | AC_SUBST([ISNAND_LIBM]) |
| 29 | ]) |
| 30 | |
| 31 | dnl Check how to get or define isnand() without linking with libm. |
| 32 | |
| 33 | AC_DEFUN([gl_FUNC_ISNAND_NO_LIBM], |
| 34 | [ |
| 35 | gl_HAVE_ISNAND_NO_LIBM |
| 36 | gl_func_isnand_no_libm=$gl_cv_func_isnand_no_libm |
| 37 | if test $gl_cv_func_isnand_no_libm = yes; then |
| 38 | AC_DEFINE([HAVE_ISNAND_IN_LIBC], [1], |
| 39 | [Define if the isnan(double) function is available in libc.]) |
| 40 | fi |
| 41 | ]) |
| 42 | |
| 43 | dnl Prerequisites of replacement isnand definition. It does not need -lm. |
| 44 | AC_DEFUN([gl_PREREQ_ISNAND], |
| 45 | [ |
| 46 | AC_REQUIRE([gl_DOUBLE_EXPONENT_LOCATION]) |
| 47 | ]) |
| 48 | |
| 49 | dnl Test whether isnand() can be used with libm. |
| 50 | |
| 51 | AC_DEFUN([gl_HAVE_ISNAND_IN_LIBM], |
| 52 | [ |
| 53 | AC_CACHE_CHECK([whether isnan(double) can be used with libm], |
| 54 | [gl_cv_func_isnand_in_libm], |
| 55 | [ |
| 56 | save_LIBS="$LIBS" |
| 57 | LIBS="$LIBS -lm" |
| 58 | AC_LINK_IFELSE( |
| 59 | [AC_LANG_PROGRAM( |
| 60 | [[#include <math.h> |
| 61 | #if __GNUC__ >= 4 |
| 62 | # undef isnand |
| 63 | # define isnand(x) __builtin_isnan ((double)(x)) |
| 64 | #elif defined isnan |
| 65 | # undef isnand |
| 66 | # define isnand(x) isnan ((double)(x)) |
| 67 | #endif |
| 68 | double x;]], |
| 69 | [[return isnand (x);]])], |
| 70 | [gl_cv_func_isnand_in_libm=yes], |
| 71 | [gl_cv_func_isnand_in_libm=no]) |
| 72 | LIBS="$save_LIBS" |
| 73 | ]) |
| 74 | ]) |
| 75 | |
| 76 | AC_DEFUN([gl_HAVE_ISNAND_NO_LIBM], |
| 77 | [ |
| 78 | AC_CACHE_CHECK([whether isnan(double) can be used without linking with libm], |
| 79 | [gl_cv_func_isnand_no_libm], |
| 80 | [ |
| 81 | AC_LINK_IFELSE( |
| 82 | [AC_LANG_PROGRAM( |
| 83 | [[#include <math.h> |
| 84 | #if __GNUC__ >= 4 |
| 85 | # undef isnand |
| 86 | # define isnand(x) __builtin_isnan ((double)(x)) |
| 87 | #else |
| 88 | # undef isnand |
| 89 | # define isnand(x) isnan ((double)(x)) |
| 90 | #endif |
| 91 | double x;]], |
| 92 | [[return isnand (x);]])], |
| 93 | [gl_cv_func_isnand_no_libm=yes], |
| 94 | [gl_cv_func_isnand_no_libm=no]) |
| 95 | ]) |
| 96 | ]) |