2 dnl Copyright (C) 2007 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_FREXPL],
9 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 AC_CACHE_CHECK([whether frexpl() can be used without linking with libm],
12 [gl_cv_func_frexpl_no_libm],
14 AC_TRY_LINK([#include <math.h>
16 [int e; return frexpl (x, &e) > 0;],
17 [gl_cv_func_frexpl_no_libm=yes],
18 [gl_cv_func_frexpl_no_libm=no])
20 if test $gl_cv_func_frexpl_no_libm = no; then
21 AC_CACHE_CHECK([whether frexpl() can be used with libm],
22 [gl_cv_func_frexpl_in_libm],
26 AC_TRY_LINK([#include <math.h>
28 [int e; return frexpl (x, &e) > 0;],
29 [gl_cv_func_frexpl_in_libm=yes],
30 [gl_cv_func_frexpl_in_libm=no])
33 if test $gl_cv_func_frexpl_in_libm = yes; then
37 if test $gl_cv_func_frexpl_no_libm = yes \
38 || test $gl_cv_func_frexpl_in_libm = yes; then
40 LIBS="$LIBS $FREXPL_LIBM"
43 case "$gl_cv_func_frexpl_works" in
44 *yes) gl_func_frexpl=yes ;;
45 *) gl_func_frexpl=no; REPLACE_FREXPL=1; FREXPL_LIBM= ;;
50 if test $gl_func_frexpl = yes; then
51 AC_DEFINE([HAVE_FREXPL], 1,
52 [Define if the frexpl() function is available.])
53 dnl Also check whether it's declared.
54 dnl MacOS X 10.3 has frexpl() in libc but doesn't declare it in <math.h>.
55 AC_CHECK_DECL([frexpl], , [HAVE_DECL_FREXPL=0], [#include <math.h>])
60 AC_SUBST([FREXPL_LIBM])
63 AC_DEFUN([gl_FUNC_FREXPL_NO_LIBM],
65 AC_REQUIRE([gl_MATH_H_DEFAULTS])
66 AC_CACHE_CHECK([whether frexpl() can be used without linking with libm],
67 [gl_cv_func_frexpl_no_libm],
69 AC_TRY_LINK([#include <math.h>
71 [int e; return frexpl (x, &e) > 0;],
72 [gl_cv_func_frexpl_no_libm=yes],
73 [gl_cv_func_frexpl_no_libm=no])
75 if test $gl_cv_func_frexpl_no_libm = yes; then
77 case "$gl_cv_func_frexpl_works" in
78 *yes) gl_func_frexpl_no_libm=yes ;;
79 *) gl_func_frexpl_no_libm=no; REPLACE_FREXPL=1 ;;
82 gl_func_frexpl_no_libm=no
83 dnl Set REPLACE_FREXPL here because the system may have frexpl in libm.
86 if test $gl_func_frexpl_no_libm = yes; then
87 AC_DEFINE([HAVE_FREXPL_IN_LIBC], 1,
88 [Define if the frexpl() function is available in libc.])
89 dnl Also check whether it's declared.
90 dnl MacOS X 10.3 has frexpl() in libc but doesn't declare it in <math.h>.
91 AC_CHECK_DECL([frexpl], , [HAVE_DECL_FREXPL=0], [#include <math.h>])
98 dnl Test whether frexpl() works on finite numbers (this fails on AIX 5.1 and
99 dnl on BeOS) and also on infinite numbers (this fails e.g. on IRIX 6.5).
100 AC_DEFUN([gl_FUNC_FREXPL_WORKS],
102 AC_REQUIRE([AC_PROG_CC])
103 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
104 AC_CACHE_CHECK([whether frexpl works], [gl_cv_func_frexpl_works],
108 extern long double frexpl (long double, int *);
111 volatile long double x;
112 /* Test on finite numbers. */
120 /* Test on large finite numbers. This fails on BeOS at i = 16322, while
121 LDBL_MAX_EXP = 16384.
122 In the loop end test, we test x against Infinity, rather than comparing
123 i with LDBL_MAX_EXP, because BeOS <float.h> has a wrong LDBL_MAX_EXP. */
126 for (i = 1, x = 1.0L; x != x + x; i++, x *= 2.0L)
134 /* Test on infinite numbers. */
138 long double y = frexpl (x, &exp);
143 }], [gl_cv_func_frexpl_works=yes], [gl_cv_func_frexpl_works=no],
145 aix* | beos* | irix*) gl_cv_func_frexpl_works="guessing no";;
146 *) gl_cv_func_frexpl_works="guessing yes";;