1 # remainder.m4 serial 3
2 dnl Copyright (C) 2012 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.
7 AC_DEFUN([gl_FUNC_REMAINDER],
9 m4_divert_text([DEFAULTS], [gl_remainder_required=plain])
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
12 dnl Test whether remainder() is declared. On IRIX 5.3 it is not declared.
13 AC_CHECK_DECL([remainder], , [HAVE_DECL_REMAINDER=0], [[#include <math.h>]])
16 AC_CACHE_CHECK([whether remainder() can be used without linking with libm],
17 [gl_cv_func_remainder_no_libm],
21 [[#ifndef __NO_MATH_INLINES
22 # define __NO_MATH_INLINES 1 /* for glibc */
27 [[return remainder (x, y) > 1;]])],
28 [gl_cv_func_remainder_no_libm=yes],
29 [gl_cv_func_remainder_no_libm=no])
31 if test $gl_cv_func_remainder_no_libm = no; then
32 AC_CACHE_CHECK([whether remainder() can be used with libm],
33 [gl_cv_func_remainder_in_libm],
39 [[#ifndef __NO_MATH_INLINES
40 # define __NO_MATH_INLINES 1 /* for glibc */
45 [[return remainder (x, y) > 1;]])],
46 [gl_cv_func_remainder_in_libm=yes],
47 [gl_cv_func_remainder_in_libm=no])
50 if test $gl_cv_func_remainder_in_libm = yes; then
54 if test $gl_cv_func_remainder_no_libm = yes \
55 || test $gl_cv_func_remainder_in_libm = yes; then
57 m4_ifdef([gl_FUNC_REMAINDER_IEEE], [
58 if test $gl_remainder_required = ieee && test $REPLACE_REMAINDER = 0; then
59 AC_CACHE_CHECK([whether remainder works according to ISO C 99 with IEC 60559],
60 [gl_cv_func_remainder_ieee],
63 LIBS="$LIBS $REMAINDER_LIBM"
66 #ifndef __NO_MATH_INLINES
67 # define __NO_MATH_INLINES 1 /* for glibc */
70 /* Compare two numbers with ==.
71 This is a separate function because IRIX 6.5 "cc -O" miscompiles an
74 numeric_equal (double x, double y)
78 static double dummy (double x, double y) { return 0; }
79 int main (int argc, char *argv[])
81 double (*my_remainder) (double, double) = argc ? remainder : dummy;
83 /* Test remainder(...,0.0).
84 This test fails on OSF/1 5.1. */
85 f = my_remainder (2.0, 0.0);
86 if (numeric_equal (f, f))
91 [gl_cv_func_remainder_ieee=yes],
92 [gl_cv_func_remainder_ieee=no],
93 [gl_cv_func_remainder_ieee="guessing no"])
96 case "$gl_cv_func_remainder_ieee" in
98 *) REPLACE_REMAINDER=1 ;;
105 if test $HAVE_REMAINDER = 0 || test $REPLACE_REMAINDER = 1; then
106 dnl Find libraries needed to link lib/remainder.c.
107 AC_REQUIRE([gl_FUNC_FABS])
108 AC_REQUIRE([gl_FUNC_FMOD])
109 AC_REQUIRE([gl_FUNC_ISNAND])
111 dnl Append $FABS_LIBM to REMAINDER_LIBM, avoiding gratuitous duplicates.
112 case " $REMAINDER_LIBM " in
114 *) REMAINDER_LIBM="$REMAINDER_LIBM $FABS_LIBM" ;;
116 dnl Append $FMOD_LIBM to REMAINDER_LIBM, avoiding gratuitous duplicates.
117 case " $REMAINDER_LIBM " in
119 *) REMAINDER_LIBM="$REMAINDER_LIBM $FMOD_LIBM" ;;
121 dnl Append $ISNAND_LIBM to REMAINDER_LIBM, avoiding gratuitous duplicates.
122 case " $REMAINDER_LIBM " in
123 *" $ISNAND_LIBM "*) ;;
124 *) REMAINDER_LIBM="$REMAINDER_LIBM $ISNAND_LIBM" ;;
127 AC_SUBST([REMAINDER_LIBM])