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_ROUNDL],
9 m4_divert_text([DEFAULTS], [gl_roundl_required=plain])
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
13 dnl Persuade glibc <math.h> to declare roundl().
14 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
16 AC_CHECK_DECLS([roundl], , , [[#include <math.h>]])
17 if test "$ac_cv_have_decl_roundl" = yes; then
18 gl_CHECK_MATH_LIB([ROUNDL_LIBM], [x = roundl (x);])
19 if test "$ROUNDL_LIBM" = missing; then
22 m4_ifdef([gl_FUNC_ROUNDL_IEEE], [
23 if test $gl_roundl_required = ieee && test $REPLACE_ROUNDL = 0; then
24 AC_CACHE_CHECK([whether roundl works according to ISO C 99 with IEC 60559],
25 [gl_cv_func_roundl_ieee],
28 LIBS="$LIBS $ROUNDL_LIBM"
31 #ifndef __NO_MATH_INLINES
32 # define __NO_MATH_INLINES 1 /* for glibc */
35 ]gl_LONG_DOUBLE_MINUS_ZERO_CODE[
36 ]gl_LONG_DOUBLE_SIGNBIT_CODE[
37 static long double dummy (long double f) { return 0; }
38 int main (int argc, char *argv[])
40 long double (*my_roundl) (long double) = argc ? roundl : dummy;
42 /* Test whether roundl (-0.0L) is -0.0L. */
43 if (signbitl (minus_zerol) && !signbitl (my_roundl (minus_zerol)))
45 /* Test whether roundl (-0.3L) is -0.0L. */
46 if (signbitl (-0.3L) && !signbitl (my_roundl (-0.3L)))
51 [gl_cv_func_roundl_ieee=yes],
52 [gl_cv_func_roundl_ieee=no],
53 [gl_cv_func_roundl_ieee="guessing no"])
56 case "$gl_cv_func_roundl_ieee" in
58 *) REPLACE_ROUNDL=1 ;;
65 if test $HAVE_DECL_ROUNDL = 0 || test $REPLACE_ROUNDL = 1; then
66 dnl Find libraries needed to link lib/roundl.c.
67 if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
68 AC_REQUIRE([gl_FUNC_ROUND])
69 ROUNDL_LIBM="$ROUND_LIBM"
71 AC_CHECK_DECLS([ceill, floorl], , , [[#include <math.h>]])
72 if test "$ac_cv_have_decl_floorl" = yes \
73 && test "$ac_cv_have_decl_ceill" = yes; then
76 if test "$FLOORL_LIBM" != '?' && test "$CEILL_LIBM" != '?'; then
77 AC_DEFINE([HAVE_FLOORL_AND_CEILL], [1],
78 [Define if the both the floorl() and ceill() functions exist.])
80 dnl Append $FLOORL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
81 case " $ROUNDL_LIBM " in
82 *" $FLOORL_LIBM "*) ;;
83 *) ROUNDL_LIBM="$ROUNDL_LIBM $FLOORL_LIBM" ;;
85 dnl Append $CEILL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
86 case " $ROUNDL_LIBM " in
88 *) ROUNDL_LIBM="$ROUNDL_LIBM $CEILL_LIBM" ;;
98 AC_SUBST([ROUNDL_LIBM])