2 dnl Copyright (C) 2010-2012 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_EXPL],
9 AC_REQUIRE([gl_MATH_H_DEFAULTS])
10 AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
12 dnl Persuade glibc <math.h> to declare expl().
13 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
16 AC_CACHE_CHECK([whether expl() can be used without linking with libm],
17 [gl_cv_func_expl_no_libm],
21 [[#ifndef __NO_MATH_INLINES
22 # define __NO_MATH_INLINES 1 /* for glibc */
25 long double (*funcptr) (long double) = expl;
27 [[return funcptr (x) > 1.5
28 || expl (x) > 1.5;]])],
29 [gl_cv_func_expl_no_libm=yes],
30 [gl_cv_func_expl_no_libm=no])
32 if test $gl_cv_func_expl_no_libm = no; then
33 AC_CACHE_CHECK([whether expl() can be used with libm],
34 [gl_cv_func_expl_in_libm],
40 [[#ifndef __NO_MATH_INLINES
41 # define __NO_MATH_INLINES 1 /* for glibc */
44 long double (*funcptr) (long double) = expl;
46 [[return funcptr (x) > 1.5
47 || expl (x) > 1.5;]])],
48 [gl_cv_func_expl_in_libm=yes],
49 [gl_cv_func_expl_in_libm=no])
52 if test $gl_cv_func_expl_in_libm = yes; then
56 if test $gl_cv_func_expl_no_libm = yes \
57 || test $gl_cv_func_expl_in_libm = yes; then
58 dnl Also check whether it's declared.
59 dnl Mac OS X 10.3 has expl() in libc but doesn't declare it in <math.h>.
60 AC_CHECK_DECL([expl], , [HAVE_DECL_EXPL=0], [[#include <math.h>]])
64 dnl Find libraries needed to link lib/expl.c.
65 if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
66 AC_REQUIRE([gl_FUNC_EXP])
69 AC_REQUIRE([gl_FUNC_ISNANL])
70 AC_REQUIRE([gl_FUNC_ROUNDL])
71 AC_REQUIRE([gl_FUNC_LDEXPL])
73 dnl Append $ISNANL_LIBM to EXPL_LIBM, avoiding gratuitous duplicates.
74 case " $EXPL_LIBM " in
75 *" $ISNANL_LIBM "*) ;;
76 *) EXPL_LIBM="$EXPL_LIBM $ISNANL_LIBM" ;;
78 dnl Append $ROUNDL_LIBM to EXPL_LIBM, avoiding gratuitous duplicates.
79 case " $EXPL_LIBM " in
80 *" $ROUNDL_LIBM "*) ;;
81 *) EXPL_LIBM="$EXPL_LIBM $ROUNDL_LIBM" ;;
83 dnl Append $LDEXPL_LIBM to EXPL_LIBM, avoiding gratuitous duplicates.
84 case " $EXPL_LIBM " in
85 *" $LDEXPL_LIBM "*) ;;
86 *) EXPL_LIBM="$EXPL_LIBM $LDEXPL_LIBM" ;;