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
|
# ilogbf.m4 serial 4
dnl Copyright (C) 2010-2020 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_ILOGBF],
[
AC_REQUIRE([gl_MATH_H_DEFAULTS])
dnl Persuade glibc <math.h> to declare ilogbf().
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
dnl Determine ILOGBF_LIBM.
gl_MATHFUNC([ilogbf], [int], [(float)])
if test $gl_cv_func_ilogbf_no_libm = yes \
|| test $gl_cv_func_ilogbf_in_libm = yes; then
save_LIBS="$LIBS"
LIBS="$LIBS $ILOGBF_LIBM"
gl_FUNC_ILOGBF_WORKS
LIBS="$save_LIBS"
case "$gl_cv_func_ilogbf_works" in
*yes) ;;
*) REPLACE_ILOGBF=1 ;;
esac
else
HAVE_ILOGBF=0
fi
if test $HAVE_ILOGBF = 0 || test $REPLACE_ILOGBF = 1; then
dnl Find libraries needed to link lib/ilogbf.c.
AC_REQUIRE([gl_FUNC_FREXPF])
AC_REQUIRE([gl_FUNC_ISNANF])
ILOGBF_LIBM=
dnl Append $FREXPF_LIBM to ILOGBF_LIBM, avoiding gratuitous duplicates.
case " $ILOGBF_LIBM " in
*" $FREXPF_LIBM "*) ;;
*) ILOGBF_LIBM="$ILOGBF_LIBM $FREXPF_LIBM" ;;
esac
dnl Append $ISNANF_LIBM to ILOGBF_LIBM, avoiding gratuitous duplicates.
case " $ILOGBF_LIBM " in
*" $ISNANF_LIBM "*) ;;
*) ILOGBF_LIBM="$ILOGBF_LIBM $ISNANF_LIBM" ;;
esac
fi
AC_SUBST([ILOGBF_LIBM])
])
dnl Test whether ilogbf() works.
dnl On OpenBSD 4.9, ilogbf(0.0) is wrong.
dnl On NetBSD 5.1, OpenBSD 4.9, ilogbf(Infinity) is wrong.
AC_DEFUN([gl_FUNC_ILOGBF_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
AC_CACHE_CHECK([whether ilogbf works], [gl_cv_func_ilogbf_works],
[
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[
#include <limits.h>
#include <math.h>
/* Provide FP_ILOGB0, FP_ILOGBNAN, like in math.in.h. */
#if defined FP_ILOGB0 && defined FP_ILOGBNAN
# if defined __HAIKU__
/* Haiku: match what ilogb() does */
# undef FP_ILOGB0
# undef FP_ILOGBNAN
# define FP_ILOGB0 (- 2147483647 - 1) /* INT_MIN */
# define FP_ILOGBNAN (- 2147483647 - 1) /* INT_MIN */
# endif
#else
# if defined __NetBSD__ || defined __sgi
/* NetBSD, IRIX 6.5: match what ilogbf() does */
# define FP_ILOGB0 INT_MIN
# define FP_ILOGBNAN INT_MIN
# elif defined _AIX
/* AIX 5.1: match what ilogbf() does in AIX >= 5.2 */
# define FP_ILOGB0 INT_MIN
# define FP_ILOGBNAN INT_MAX
# elif defined __sun
/* Solaris 9: match what ilogbf() does */
# define FP_ILOGB0 (- INT_MAX)
# define FP_ILOGBNAN INT_MAX
# endif
#endif
volatile float x;
static float zero;
static int dummy (float x) { return 0; }
int main (int argc, char *argv[])
{
int (* volatile my_ilogbf) (float) = argc ? ilogbf : dummy;
int result = 0;
/* This test fails on OpenBSD 4.9. */
{
x = 0.0f;
if (my_ilogbf (x) != FP_ILOGB0)
result |= 1;
}
/* This test fails on NetBSD 5.1, OpenBSD 4.9. */
{
x = 1.0f / zero;
if (my_ilogbf (x) != INT_MAX)
result |= 2;
}
return result;
}
]])],
[gl_cv_func_ilogbf_works=yes],
[gl_cv_func_ilogbf_works=no],
[case "$host_os" in
openbsd* | netbsd*)
gl_cv_func_ilogbf_works="guessing no" ;;
# Guess yes on native Windows.
mingw*) gl_cv_func_ilogbf_works="guessing yes" ;;
*) gl_cv_func_ilogbf_works="guessing yes" ;;
esac
])
])
])
|
