summaryrefslogtreecommitdiff
path: root/m4/remainderf.m4
blob: 484cfa91568f819eec255ca4f463d30ac6b01a7d (plain)
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
# remainderf.m4 serial 8
dnl Copyright (C) 2012-2015 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_REMAINDERF],
[
  m4_divert_text([DEFAULTS], [gl_remainderf_required=plain])
  AC_REQUIRE([gl_MATH_H_DEFAULTS])
  AC_REQUIRE([gl_FUNC_REMAINDER])

  dnl Persuade glibc <math.h> to declare remainderf().
  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])

  dnl Test whether remainderf() exists. Assume that remainderf(), if it exists, is
  dnl defined in the same library as remainder().
  save_LIBS="$LIBS"
  LIBS="$LIBS $REMAINDER_LIBM"
  AC_CACHE_CHECK([for remainderf],
    [gl_cv_func_remainderf],
    [
      AC_LINK_IFELSE(
        [AC_LANG_PROGRAM(
           [[#ifndef __NO_MATH_INLINES
             # define __NO_MATH_INLINES 1 /* for glibc */
             #endif
             #include <math.h>
             extern
             #ifdef __cplusplus
             "C"
             #endif
             float remainderf (float, float);
             float (*funcptr) (float, float) = remainderf;
             float x;
             float y;]],
           [[return funcptr (x, y) > 1
                    || remainderf (x, y) > 1;]])],
        [gl_cv_func_remainderf=yes],
        [gl_cv_func_remainderf=no])
    ])
  LIBS="$save_LIBS"
  if test $gl_cv_func_remainderf = yes; then
    REMAINDERF_LIBM="$REMAINDER_LIBM"

    save_LIBS="$LIBS"
    LIBS="$LIBS $REMAINDERF_LIBM"
    gl_FUNC_REMAINDERF_WORKS
    LIBS="$save_LIBS"
    case "$gl_cv_func_remainderf_works" in
      *yes) ;;
      *) REPLACE_REMAINDERF=1 ;;
    esac

    m4_ifdef([gl_FUNC_REMAINDERF_IEEE], [
      if test $gl_remainderf_required = ieee && test $REPLACE_REMAINDERF = 0; then
        AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
        AC_CACHE_CHECK([whether remainderf works according to ISO C 99 with IEC 60559],
          [gl_cv_func_remainderf_ieee],
          [
            save_LIBS="$LIBS"
            LIBS="$LIBS $REMAINDERF_LIBM"
            AC_RUN_IFELSE(
              [AC_LANG_SOURCE([[
#ifndef __NO_MATH_INLINES
# define __NO_MATH_INLINES 1 /* for glibc */
#endif
#include <math.h>
extern
#ifdef __cplusplus
"C"
#endif
float remainderf (float, float);
/* Compare two numbers with ==.
   This is a separate function because IRIX 6.5 "cc -O" miscompiles an
   'x == x' test.  */
static int
numeric_equal (float x, float y)
{
  return x == y;
}
static float dummy (float x, float y) { return 0; }
int main (int argc, char *argv[])
{
  float (*my_remainderf) (float, float) = argc ? remainderf : dummy;
  float f;
  /* Test remainderf(...,0.0f).
     This test fails on OSF/1 5.1.  */
  f = my_remainderf (2.0f, 0.0f);
  if (numeric_equal (f, f))
    return 1;
  return 0;
}
              ]])],
              [gl_cv_func_remainderf_ieee=yes],
              [gl_cv_func_remainderf_ieee=no],
              [case "$host_os" in
                         # Guess yes on glibc systems.
                 *-gnu*) gl_cv_func_remainderf_ieee="guessing yes" ;;
                         # If we don't know, assume the worst.
                 *)      gl_cv_func_remainderf_ieee="guessing no" ;;
               esac
              ])
            LIBS="$save_LIBS"
          ])
        case "$gl_cv_func_remainderf_ieee" in
          *yes) ;;
          *) REPLACE_REMAINDERF=1 ;;
        esac
      fi
    ])
  else
    HAVE_REMAINDERF=0
  fi
  if test $HAVE_REMAINDERF = 0 || test $REPLACE_REMAINDERF = 1; then
    dnl Find libraries needed to link lib/remainderf.c.
    if test $gl_cv_func_remainder_no_libm = yes \
       || test $gl_cv_func_remainder_in_libm = yes; then
      AC_DEFINE([HAVE_REMAINDER], [1],
        [Define to 1 if the remainder() function is available in libc or libm.])
      REMAINDERF_LIBM="$REMAINDER_LIBM"
    else
      AC_REQUIRE([gl_FUNC_FABSF])
      AC_REQUIRE([gl_FUNC_FMODF])
      AC_REQUIRE([gl_FUNC_ISNANF])
      REMAINDERF_LIBM=
      dnl Append $FABSF_LIBM to REMAINDERF_LIBM, avoiding gratuitous duplicates.
      case " $REMAINDERF_LIBM " in
        *" $FABSF_LIBM "*) ;;
        *) REMAINDERF_LIBM="$REMAINDERF_LIBM $FABSF_LIBM" ;;
      esac
      dnl Append $FMODF_LIBM to REMAINDERF_LIBM, avoiding gratuitous duplicates.
      case " $REMAINDERF_LIBM " in
        *" $FMODF_LIBM "*) ;;
        *) REMAINDERF_LIBM="$REMAINDERF_LIBM $FMODF_LIBM" ;;
      esac
      dnl Append $ISNANF_LIBM to REMAINDERF_LIBM, avoiding gratuitous duplicates.
      case " $REMAINDERF_LIBM " in
        *" $ISNANF_LIBM "*) ;;
        *) REMAINDERF_LIBM="$REMAINDERF_LIBM $ISNANF_LIBM" ;;
      esac
    fi
  fi
  AC_SUBST([REMAINDERF_LIBM])
])

dnl Test whether remainderf() works.
dnl It runs into an endless loop on IRIX 6.5.
AC_DEFUN([gl_FUNC_REMAINDERF_WORKS],
[
  AC_REQUIRE([AC_PROG_CC])
  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
  AC_CHECK_DECLS_ONCE([alarm])
  AC_CACHE_CHECK([whether remainderf works], [gl_cv_func_remainderf_works],
    [
      AC_RUN_IFELSE(
        [AC_LANG_SOURCE([[
#include <math.h>
#if HAVE_DECL_ALARM
# include <signal.h>
# include <unistd.h>
#endif
extern
#ifdef __cplusplus
"C"
#endif
float remainderf (float, float);
volatile float x;
volatile float y;
float z;
int main ()
{
#if HAVE_DECL_ALARM
  signal (SIGALRM, SIG_DFL);
  alarm (5);
#endif
  /* This test fails on IRIX 6.5.  */
  x = 9.316161e+37f;
  y = 0.5475547314f;
  z = remainderf (x, y);
  return 0;
}
]])],
        [gl_cv_func_remainderf_works=yes],
        [gl_cv_func_remainderf_works=no],
        [case "$host_os" in
           irix*) gl_cv_func_remainderf_works="guessing no";;
           *)     gl_cv_func_remainderf_works="guessing yes";;
         esac
        ])
    ])
])