2 dnl Copyright (C) 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_HYPOTF],
9 m4_divert_text([DEFAULTS], [gl_hypotf_required=plain])
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 AC_REQUIRE([gl_FUNC_HYPOT])
13 dnl Test whether hypotf() exists. Assume that hypotf(), if it exists, is
14 dnl defined in the same library as hypot().
16 LIBS="$LIBS $HYPOT_LIBM"
17 AC_CHECK_FUNCS([hypotf])
19 if test $ac_cv_func_hypotf = yes; then
20 HYPOTF_LIBM="$HYPOT_LIBM"
22 LIBS="$LIBS $HYPOTF_LIBM"
25 case "$gl_cv_func_hypotf_works" in
27 *) REPLACE_HYPOTF=1 ;;
29 m4_ifdef([gl_FUNC_HYPOTF_IEEE], [
30 if test $gl_hypotf_required = ieee && test $REPLACE_HYPOTF = 0; then
31 AC_CACHE_CHECK([whether hypotf works according to ISO C 99 with IEC 60559],
32 [gl_cv_func_hypotf_ieee],
35 LIBS="$LIBS $HYPOTF_LIBM"
38 #ifndef __NO_MATH_INLINES
39 # define __NO_MATH_INLINES 1 /* for glibc */
42 /* Compare two numbers with ==.
43 This is a separate function because IRIX 6.5 "cc -O" miscompiles an
46 numeric_equal (float x, float y)
50 static float dummy (float x, float y) { return 0; }
53 int main (int argc, char *argv[])
55 float (*my_hypotf) (float, float) = argc ? hypotf : dummy;
57 /* Test hypotf(NaN,Infinity).
58 This test fails on OSF/1 5.1 and native Windows. */
59 f = my_hypotf (zero / zero, one / zero);
60 if (!numeric_equal (f, f))
65 [gl_cv_func_hypotf_ieee=yes],
66 [gl_cv_func_hypotf_ieee=no],
67 [gl_cv_func_hypotf_ieee="guessing no"])
70 case "$gl_cv_func_hypotf_ieee" in
72 *) REPLACE_HYPOTF=1 ;;
79 if test $HAVE_HYPOTF = 0 || test $REPLACE_HYPOTF = 1; then
80 dnl Find libraries needed to link lib/hypotf.c.
81 HYPOTF_LIBM="$HYPOT_LIBM"
83 AC_SUBST([HYPOTF_LIBM])
86 dnl Test whether hypotf() works.
87 dnl It returns wrong values on NetBSD 5.1/x86_64 and OpenBSD 4.9/x86.
88 AC_DEFUN([gl_FUNC_HYPOTF_WORKS],
90 AC_REQUIRE([AC_PROG_CC])
91 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
92 AC_CACHE_CHECK([whether hypotf works], [gl_cv_func_hypotf_works],
104 /* This test fails on NetBSD 5.1. */
109 if (!(z >= FLT_MIN * 2.0f && z <= FLT_MIN * 4.0f))
112 /* This test fails on OpenBSD 4.9. */
117 if (!(z > 0 && z == z + z))
123 [gl_cv_func_hypotf_works=yes],
124 [gl_cv_func_hypotf_works=no],
126 netbsd* | openbsd*) gl_cv_func_hypotf_works="guessing no";;
127 *) gl_cv_func_hypotf_works="guessing yes";;