3 dnl Copyright (C) 2010-2024 Free Software Foundation, Inc.
4 dnl This file is free software; the Free Software Foundation
5 dnl gives unlimited permission to copy and/or distribute it,
6 dnl with or without modifications, as long as this notice is preserved.
8 AC_DEFUN([gl_FUNC_TANL],
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
13 dnl Persuade glibc <math.h> to declare tanl().
14 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
17 AC_CACHE_CHECK([whether tanl() can be used without linking with libm],
18 [gl_cv_func_tanl_no_libm],
22 [[#ifndef __NO_MATH_INLINES
23 # define __NO_MATH_INLINES 1 /* for glibc */
26 long double (* volatile funcptr) (long double) = tanl;
28 [[return funcptr (x) > 0.4
29 || tanl (x) > 0.4;]])],
30 [gl_cv_func_tanl_no_libm=yes],
31 [gl_cv_func_tanl_no_libm=no])
33 if test $gl_cv_func_tanl_no_libm = no; then
34 AC_CACHE_CHECK([whether tanl() can be used with libm],
35 [gl_cv_func_tanl_in_libm],
41 [[#ifndef __NO_MATH_INLINES
42 # define __NO_MATH_INLINES 1 /* for glibc */
45 long double (* volatile funcptr) (long double) = tanl;
47 [[return funcptr (x) > 0.4
48 || tanl (x) > 0.4;]])],
49 [gl_cv_func_tanl_in_libm=yes],
50 [gl_cv_func_tanl_in_libm=no])
53 if test $gl_cv_func_tanl_in_libm = yes; then
57 if test $gl_cv_func_tanl_no_libm = yes \
58 || test $gl_cv_func_tanl_in_libm = yes; then
59 dnl Also check whether it's declared.
60 dnl Mac OS X 10.3 has tanl() in libc but doesn't declare it in <math.h>.
61 AC_CHECK_DECL([tanl], , [HAVE_DECL_TANL=0], [[#include <math.h>]])
65 dnl Find libraries needed to link lib/tanl.c, lib/trigl.c.
66 if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
67 AC_REQUIRE([gl_FUNC_TAN])
70 AC_REQUIRE([gl_FUNC_ISNANL])
71 AC_REQUIRE([gl_FUNC_FLOOR])
72 AC_REQUIRE([gl_FUNC_FLOORL])
73 dnl Append $ISNANL_LIBM to TANL_LIBM, avoiding gratuitous duplicates.
74 case " $TANL_LIBM " in
75 *" $ISNANL_LIBM "*) ;;
76 *) TANL_LIBM="$TANL_LIBM $ISNANL_LIBM" ;;
78 dnl Append $FLOOR_LIBM to TANL_LIBM, avoiding gratuitous duplicates.
79 case " $TANL_LIBM " in
81 *) TANL_LIBM="$TANL_LIBM $FLOOR_LIBM" ;;
83 dnl Append $FLOORL_LIBM to TANL_LIBM, avoiding gratuitous duplicates.
84 case " $TANL_LIBM " in
85 *" $FLOORL_LIBM "*) ;;
86 *) TANL_LIBM="$TANL_LIBM $FLOORL_LIBM" ;;