1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231
|
# frexpl.m4 serial 21
dnl Copyright (C) 2007-2020 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.
AC_DEFUN([gl_FUNC_FREXPL],
[
AC_REQUIRE([gl_MATH_H_DEFAULTS])
AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
dnl Persuade glibc <math.h> to declare frexpl().
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
dnl Check whether it's declared.
dnl Mac OS 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>]])
FREXPL_LIBM=
if test $HAVE_DECL_FREXPL = 1; then
gl_CHECK_FREXPL_NO_LIBM
if test $gl_cv_func_frexpl_no_libm = no; then
AC_CACHE_CHECK([whether frexpl() can be used with libm],
[gl_cv_func_frexpl_in_libm],
[
save_LIBS="$LIBS"
LIBS="$LIBS -lm"
AC_LINK_IFELSE(
[AC_LANG_PROGRAM(
[[#include <math.h>
long double x;]],
[[int e; return frexpl (x, &e) > 0;]])],
[gl_cv_func_frexpl_in_libm=yes],
[gl_cv_func_frexpl_in_libm=no])
LIBS="$save_LIBS"
])
if test $gl_cv_func_frexpl_in_libm = yes; then
FREXPL_LIBM=-lm
fi
fi
if test $gl_cv_func_frexpl_no_libm = yes \
|| test $gl_cv_func_frexpl_in_libm = yes; then
save_LIBS="$LIBS"
LIBS="$LIBS $FREXPL_LIBM"
gl_FUNC_FREXPL_WORKS
LIBS="$save_LIBS"
case "$gl_cv_func_frexpl_works" in
*yes) gl_func_frexpl=yes ;;
*) gl_func_frexpl=no; REPLACE_FREXPL=1 ;;
esac
else
gl_func_frexpl=no
fi
if test $gl_func_frexpl = yes; then
AC_DEFINE([HAVE_FREXPL], [1],
[Define if the frexpl() function is available.])
fi
fi
if test $HAVE_DECL_FREXPL = 0 || test $gl_func_frexpl = no; then
dnl Find libraries needed to link lib/frexpl.c.
if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
AC_REQUIRE([gl_FUNC_FREXP])
FREXPL_LIBM="$FREXP_LIBM"
else
FREXPL_LIBM=
fi
fi
AC_SUBST([FREXPL_LIBM])
])
AC_DEFUN([gl_FUNC_FREXPL_NO_LIBM],
[
AC_REQUIRE([gl_MATH_H_DEFAULTS])
AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
dnl Check whether it's declared.
dnl Mac OS 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>]])
if test $HAVE_DECL_FREXPL = 1; then
gl_CHECK_FREXPL_NO_LIBM
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.])
fi
fi
])
dnl Test whether frexpl() can be used without linking with libm.
dnl Set gl_cv_func_frexpl_no_libm to 'yes' or 'no' accordingly.
AC_DEFUN([gl_CHECK_FREXPL_NO_LIBM],
[
AC_CACHE_CHECK([whether frexpl() can be used without linking with libm],
[gl_cv_func_frexpl_no_libm],
[
AC_LINK_IFELSE(
[AC_LANG_PROGRAM(
[[#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])
])
])
dnl Test whether frexpl() works on finite numbers (this fails on
dnl Mac OS X 10.4/PowerPC, on AIX 5.1, and on BeOS), on denormalized numbers
dnl (this fails on Mac OS X 10.5/i386), and also on infinite numbers (this
dnl fails e.g. on IRIX 6.5 and mingw).
AC_DEFUN([gl_FUNC_FREXPL_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
AC_CACHE_CHECK([whether frexpl works], [gl_cv_func_frexpl_works],
[
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[
#include <float.h>
#include <math.h>
/* Override the values of <float.h>, like done in float.in.h. */
#if defined __i386__ && (defined __BEOS__ || defined __OpenBSD__)
# undef LDBL_MIN_EXP
# define LDBL_MIN_EXP (-16381)
#endif
#if defined __i386__ && (defined __FreeBSD__ || defined __DragonFly__)
# undef LDBL_MIN_EXP
# define LDBL_MIN_EXP (-16381)
#endif
#if (defined _ARCH_PPC || defined _POWER) && defined _AIX && (LDBL_MANT_DIG == 106) && defined __GNUC__
# undef LDBL_MIN_EXP
# define LDBL_MIN_EXP DBL_MIN_EXP
#endif
#if defined __sgi && (LDBL_MANT_DIG >= 106)
# if defined __GNUC__
# undef LDBL_MIN_EXP
# define LDBL_MIN_EXP DBL_MIN_EXP
# endif
#endif
extern
#ifdef __cplusplus
"C"
#endif
long double frexpl (long double, int *);
int main()
{
int result = 0;
volatile long double x;
/* Test on finite numbers that fails on AIX 5.1. */
x = 16.0L;
{
int exp = -9999;
frexpl (x, &exp);
if (exp != 5)
result |= 1;
}
/* Test on finite numbers that fails on Mac OS X 10.4, because its frexpl
function returns an invalid (incorrectly normalized) value: it returns
y = { 0x3fe028f5, 0xc28f5c28, 0x3c9eb851, 0xeb851eb8 }
but the correct result is
0.505L = { 0x3fe028f5, 0xc28f5c29, 0xbc547ae1, 0x47ae1480 } */
x = 1.01L;
{
int exp = -9999;
long double y = frexpl (x, &exp);
if (!(exp == 1 && y == 0.505L))
result |= 2;
}
/* Test on large finite numbers. This fails on BeOS at i = 16322, while
LDBL_MAX_EXP = 16384.
In the loop end test, we test x against Infinity, rather than comparing
i with LDBL_MAX_EXP, because BeOS <float.h> has a wrong LDBL_MAX_EXP. */
{
int i;
for (i = 1, x = 1.0L; x != x + x; i++, x *= 2.0L)
{
int exp = -9999;
frexpl (x, &exp);
if (exp != i)
{
result |= 4;
break;
}
}
}
/* Test on denormalized numbers. */
{
int i;
for (i = 1, x = 1.0L; i >= LDBL_MIN_EXP; i--, x *= 0.5L)
;
if (x > 0.0L)
{
int exp;
long double y = frexpl (x, &exp);
/* On machines with IEEE854 arithmetic: x = 1.68105e-4932,
exp = -16382, y = 0.5. On Mac OS X 10.5: exp = -16384, y = 0.5. */
if (exp != LDBL_MIN_EXP - 1)
result |= 8;
}
}
/* Test on infinite numbers. */
x = 1.0L / 0.0L;
{
int exp;
long double y = frexpl (x, &exp);
if (y != x)
result |= 16;
}
return result;
}]])],
[gl_cv_func_frexpl_works=yes],
[gl_cv_func_frexpl_works=no],
[
changequote(,)dnl
case "$host_os" in
aix | aix[3-6]* | beos* | darwin* | irix* | mingw* | pw*)
gl_cv_func_frexpl_works="guessing no";;
*) gl_cv_func_frexpl_works="guessing yes";;
esac
changequote([,])dnl
])
])
])
|