2 dnl Copyright (C) 2007, 2009-2012 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_CEIL],
9 m4_divert_text([DEFAULTS], [gl_ceil_required=plain])
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 dnl Test whether ceil() can be used without libm.
13 if test "$CEIL_LIBM" = "?"; then
16 m4_ifdef([gl_FUNC_CEIL_IEEE], [
17 if test $gl_ceil_required = ieee && test $REPLACE_CEIL = 0; then
18 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
19 AC_CACHE_CHECK([whether ceil works according to ISO C 99 with IEC 60559],
20 [gl_cv_func_ceil_ieee],
23 LIBS="$LIBS $CEIL_LIBM"
26 #ifndef __NO_MATH_INLINES
27 # define __NO_MATH_INLINES 1 /* for glibc */
30 ]gl_DOUBLE_MINUS_ZERO_CODE[
31 ]gl_DOUBLE_SIGNBIT_CODE[
32 static double dummy (double f) { return 0; }
33 int main (int argc, char *argv[])
35 double (*my_ceil) (double) = argc ? ceil : dummy;
37 /* Test whether ceil (-0.0) is -0.0. */
38 if (signbitd (minus_zerod) && !signbitd (my_ceil (minus_zerod)))
40 /* Test whether ceil (-0.3) is -0.0. */
41 if (signbitd (-0.3) && !signbitd (my_ceil (-0.3)))
46 [gl_cv_func_ceil_ieee=yes],
47 [gl_cv_func_ceil_ieee=no],
49 # Guess yes on glibc systems.
50 *-gnu*) gl_cv_func_ceil_ieee="guessing yes" ;;
51 # If we don't know, assume the worst.
52 *) gl_cv_func_ceil_ieee="guessing no" ;;
57 case "$gl_cv_func_ceil_ieee" in
63 if test $REPLACE_CEIL = 1; then
64 dnl No libraries are needed to link lib/ceil.c.
70 # Determines the libraries needed to get the ceil() function.
72 AC_DEFUN([gl_FUNC_CEIL_LIBS],
74 gl_CACHE_VAL_SILENT([gl_cv_func_ceil_libm], [
75 gl_cv_func_ceil_libm=?
78 [[#ifndef __NO_MATH_INLINES
79 # define __NO_MATH_INLINES 1 /* for glibc */
84 [gl_cv_func_ceil_libm=])
85 if test "$gl_cv_func_ceil_libm" = "?"; then
90 [[#ifndef __NO_MATH_INLINES
91 # define __NO_MATH_INLINES 1 /* for glibc */
96 [gl_cv_func_ceil_libm="-lm"])
100 CEIL_LIBM="$gl_cv_func_ceil_libm"