2 dnl Copyright (C) 2007, 2009-2011 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_FLOOR],
9 m4_divert_text([DEFAULTS], [gl_floor_required=plain])
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 dnl Test whether floor() can be used without libm.
13 if test "$FLOOR_LIBM" = "?"; then
16 m4_ifdef([gl_FUNC_FLOOR_IEEE], [
17 if test $gl_floor_required = ieee && test $REPLACE_FLOOR = 0; then
18 AC_CACHE_CHECK([whether floor works according to ISO C 99 with IEC 60559],
19 [gl_cv_func_floor_ieee],
22 LIBS="$LIBS $FLOOR_LIBM"
25 #ifndef __NO_MATH_INLINES
26 # define __NO_MATH_INLINES 1 /* for glibc */
29 ]gl_DOUBLE_MINUS_ZERO_CODE[
30 ]gl_DOUBLE_SIGNBIT_CODE[
33 /* Test whether floor (-0.0) is -0.0. */
34 if (signbitd (minus_zerod) && !signbitd (floor (minus_zerod)))
39 [gl_cv_func_floor_ieee=yes],
40 [gl_cv_func_floor_ieee=no],
41 [gl_cv_func_floor_ieee="guessing no"])
44 case "$gl_cv_func_floor_ieee" in
50 if test $REPLACE_FLOOR = 1; then
54 AC_SUBST([FLOOR_LIBM])
57 # Determines the libraries needed to get the floor() function.
59 AC_DEFUN([gl_FUNC_FLOOR_LIBS],
61 gl_CACHE_VAL_SILENT([gl_cv_func_floor_libm], [
62 gl_cv_func_floor_libm=?
65 [[#ifndef __NO_MATH_INLINES
66 # define __NO_MATH_INLINES 1 /* for glibc */
71 [gl_cv_func_floor_libm=])
72 if test "$gl_cv_func_floor_libm" = "?"; then
77 [[#ifndef __NO_MATH_INLINES
78 # define __NO_MATH_INLINES 1 /* for glibc */
83 [gl_cv_func_floor_libm="-lm"])
87 FLOOR_LIBM="$gl_cv_func_floor_libm"