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 dnl Persuade glibc <math.h> to declare roundl().
12 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
13 AC_CHECK_DECLS([roundl], , , [#include <math.h>])
14 if test "$ac_cv_have_decl_roundl" = yes; then
15 gl_CHECK_MATH_LIB([ROUNDL_LIBM], [x = roundl (x);])
16 if test "$ROUNDL_LIBM" = missing; then
19 m4_ifdef([gl_FUNC_ROUNDL_IEEE], [
20 if test $gl_roundl_required = ieee && test $REPLACE_ROUNDL = 0; then
21 AC_CACHE_CHECK([whether roundl works according to ISO C 99 with IEC 60559],
22 [gl_cv_func_roundl_ieee],
25 LIBS="$LIBS $ROUNDL_LIBM"
28 #ifndef __NO_MATH_INLINES
29 # define __NO_MATH_INLINES 1 /* for glibc */
32 ]gl_LONG_DOUBLE_MINUS_ZERO_CODE[
33 ]gl_LONG_DOUBLE_SIGNBIT_CODE[
34 static long double dummy (long double f) { return 0; }
35 int main (int argc, char *argv[])
37 long double (*my_roundl) (long double) = argc ? roundl : dummy;
39 /* Test whether roundl (-0.0L) is -0.0L. */
40 if (signbitl (minus_zerol) && !signbitl (my_roundl (minus_zerol)))
42 /* Test whether roundl (-0.3L) is -0.0L. */
43 if (signbitl (-0.3L) && !signbitl (my_roundl (-0.3L)))
48 [gl_cv_func_roundl_ieee=yes],
49 [gl_cv_func_roundl_ieee=no],
50 [gl_cv_func_roundl_ieee="guessing no"])
53 case "$gl_cv_func_roundl_ieee" in
55 *) REPLACE_ROUNDL=1 ;;
62 if test $HAVE_DECL_ROUNDL = 0 || test $REPLACE_ROUNDL = 1; then
63 dnl Find libraries needed to link lib/roundl.c.
64 AC_CHECK_DECLS([ceill, floorl], , , [#include <math.h>])
65 if test "$ac_cv_have_decl_floorl" = yes \
66 && test "$ac_cv_have_decl_ceill" = yes; then
69 if test "$FLOORL_LIBM" != '?' && test "$CEILL_LIBM" != '?'; then
70 AC_DEFINE([HAVE_FLOORL_AND_CEILL], [1],
71 [Define if the both the floorl() and ceill() functions exist.])
73 dnl Append $FLOORL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
74 case " $ROUNDL_LIBM " in
75 *" $FLOORL_LIBM "*) ;;
76 *) ROUNDL_LIBM="$ROUNDL_LIBM $FLOORL_LIBM" ;;
78 dnl Append $CEILL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
79 case " $ROUNDL_LIBM " in
81 *) ROUNDL_LIBM="$ROUNDL_LIBM $CEILL_LIBM" ;;
90 AC_SUBST([ROUNDL_LIBM])