2 dnl Copyright (C) 2007, 2009-2012 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_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 gl_CHECK_MATH_LIB([ROUNDL_LIBM], [x = roundl (x);],
21 long double roundl (long double);
23 if test "$ROUNDL_LIBM" != missing; then
25 dnl Also check whether it's declared.
26 dnl IRIX 6.5 has roundl() in libm but doesn't declare it in <math.h>.
27 AC_CHECK_DECLS([roundl], , [HAVE_DECL_ROUNDL=0], [[#include <math.h>]])
29 m4_ifdef([gl_FUNC_ROUNDL_IEEE], [
30 if test $gl_roundl_required = ieee && test $REPLACE_ROUNDL = 0; then
31 AC_CACHE_CHECK([whether roundl works according to ISO C 99 with IEC 60559],
32 [gl_cv_func_roundl_ieee],
35 LIBS="$LIBS $ROUNDL_LIBM"
38 #ifndef __NO_MATH_INLINES
39 # define __NO_MATH_INLINES 1 /* for glibc */
46 long double roundl (long double);
47 ]gl_LONG_DOUBLE_MINUS_ZERO_CODE[
48 ]gl_LONG_DOUBLE_SIGNBIT_CODE[
49 static long double dummy (long double f) { return 0; }
50 int main (int argc, char *argv[])
52 long double (*my_roundl) (long double) = argc ? roundl : dummy;
54 /* Test whether roundl (-0.0L) is -0.0L. */
55 if (signbitl (minus_zerol) && !signbitl (my_roundl (minus_zerol)))
57 /* Test whether roundl (-0.3L) is -0.0L. */
58 if (signbitl (-0.3L) && !signbitl (my_roundl (-0.3L)))
63 [gl_cv_func_roundl_ieee=yes],
64 [gl_cv_func_roundl_ieee=no],
65 [gl_cv_func_roundl_ieee="guessing no"])
68 case "$gl_cv_func_roundl_ieee" in
70 *) REPLACE_ROUNDL=1 ;;
78 if test $HAVE_ROUNDL = 0 || test $REPLACE_ROUNDL = 1; then
79 dnl Find libraries needed to link lib/roundl.c.
80 if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
81 AC_REQUIRE([gl_FUNC_ROUND])
82 ROUNDL_LIBM="$ROUND_LIBM"
84 AC_CHECK_DECLS([ceill, floorl], , , [[#include <math.h>]])
85 if test "$ac_cv_have_decl_floorl" = yes \
86 && test "$ac_cv_have_decl_ceill" = yes; then
89 if test "$FLOORL_LIBM" != '?' && test "$CEILL_LIBM" != '?'; then
90 AC_DEFINE([HAVE_FLOORL_AND_CEILL], [1],
91 [Define if the both the floorl() and ceill() functions exist.])
93 dnl Append $FLOORL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
94 case " $ROUNDL_LIBM " in
95 *" $FLOORL_LIBM "*) ;;
96 *) ROUNDL_LIBM="$ROUNDL_LIBM $FLOORL_LIBM" ;;
98 dnl Append $CEILL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
99 case " $ROUNDL_LIBM " in
100 *" $CEILL_LIBM "*) ;;
101 *) ROUNDL_LIBM="$ROUNDL_LIBM $CEILL_LIBM" ;;
111 AC_SUBST([ROUNDL_LIBM])