2 dnl Copyright (C) 2011-2012 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_FMODF],
9 m4_divert_text([DEFAULTS], [gl_fmodf_required=plain])
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 AC_REQUIRE([gl_FUNC_FMOD])
13 dnl Persuade glibc <math.h> to declare fmodf().
14 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
16 dnl Test whether fmodf() exists. Assume that fmodf(), if it exists, is
17 dnl defined in the same library as fmod().
19 LIBS="$LIBS $FMOD_LIBM"
20 AC_CHECK_FUNCS([fmodf])
22 if test $ac_cv_func_fmodf = yes; then
23 FMODF_LIBM="$FMOD_LIBM"
24 m4_ifdef([gl_FUNC_FMODF_IEEE], [
25 if test $gl_fmodf_required = ieee && test $REPLACE_FMODF = 0; then
26 AC_CACHE_CHECK([whether fmodf works according to ISO C 99 with IEC 60559],
27 [gl_cv_func_fmodf_ieee],
30 LIBS="$LIBS $FMODF_LIBM"
33 #ifndef __NO_MATH_INLINES
34 # define __NO_MATH_INLINES 1 /* for glibc */
37 /* Compare two numbers with ==.
38 This is a separate function because IRIX 6.5 "cc -O" miscompiles an
41 numeric_equal (float x, float y)
45 static float dummy (float x, float y) { return 0; }
46 int main (int argc, char *argv[])
48 float (*my_fmodf) (float, float) = argc ? fmodf : dummy;
50 /* Test fmodf(...,0.0f).
51 This test fails on OSF/1 5.1. */
52 f = my_fmodf (2.0f, 0.0f);
53 if (numeric_equal (f, f))
58 [gl_cv_func_fmodf_ieee=yes],
59 [gl_cv_func_fmodf_ieee=no],
60 [gl_cv_func_fmodf_ieee="guessing no"])
63 case "$gl_cv_func_fmodf_ieee" in
72 if test $HAVE_FMODF = 0 || test $REPLACE_FMODF = 1; then
73 dnl Find libraries needed to link lib/fmodf.c.
74 FMODF_LIBM="$FMOD_LIBM"
76 AC_SUBST([FMODF_LIBM])