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_FLOORF],
9 m4_divert_text([DEFAULTS], [gl_floorf_required=plain])
10 AC_REQUIRE([gl_MATH_H_DEFAULTS])
11 dnl Persuade glibc <math.h> to declare floorf().
12 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
13 dnl Test whether floorf() is declared.
14 AC_CHECK_DECLS([floorf], , , [[#include <math.h>]])
15 if test "$ac_cv_have_decl_floorf" = yes; then
16 dnl Test whether floorf() can be used without libm.
18 if test "$FLOORF_LIBM" = "?"; then
19 dnl Sun C 5.0 on Solaris declares floorf() and has it in the system-wide
20 dnl libm.so, but not in the libm.so that the compiler uses.
23 m4_ifdef([gl_FUNC_FLOORF_IEEE], [
24 if test $gl_floorf_required = ieee && test $REPLACE_FLOORF = 0; then
25 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
26 AC_CACHE_CHECK([whether floorf works according to ISO C 99 with IEC 60559],
27 [gl_cv_func_floorf_ieee],
30 LIBS="$LIBS $FLOORF_LIBM"
33 #ifndef __NO_MATH_INLINES
34 # define __NO_MATH_INLINES 1 /* for glibc */
37 ]gl_FLOAT_MINUS_ZERO_CODE[
38 ]gl_FLOAT_SIGNBIT_CODE[
39 static float dummy (float f) { return 0; }
40 int main (int argc, char *argv[])
42 float (*my_floorf) (float) = argc ? floorf : dummy;
43 /* Test whether floorf (-0.0f) is -0.0f. */
44 if (signbitf (minus_zerof) && !signbitf (my_floorf (minus_zerof)))
49 [gl_cv_func_floorf_ieee=yes],
50 [gl_cv_func_floorf_ieee=no],
52 # Guess yes on glibc systems.
53 *-gnu*) gl_cv_func_floorf_ieee="guessing yes" ;;
54 # If we don't know, assume the worst.
55 *) gl_cv_func_floorf_ieee="guessing no" ;;
60 case "$gl_cv_func_floorf_ieee" in
62 *) REPLACE_FLOORF=1 ;;
69 if test $HAVE_DECL_FLOORF = 0 || test $REPLACE_FLOORF = 1; then
70 dnl No libraries are needed to link lib/floorf.c.
73 AC_SUBST([FLOORF_LIBM])
76 # Determines the libraries needed to get the floorf() function.
78 AC_DEFUN([gl_FUNC_FLOORF_LIBS],
80 gl_CACHE_VAL_SILENT([gl_cv_func_floorf_libm], [
81 gl_cv_func_floorf_libm=?
84 [[#ifndef __NO_MATH_INLINES
85 # define __NO_MATH_INLINES 1 /* for glibc */
88 float (*funcptr) (float) = floorf;
90 [[x = funcptr(x) + floorf(x);]])],
91 [gl_cv_func_floorf_libm=])
92 if test "$gl_cv_func_floorf_libm" = "?"; then
97 [[#ifndef __NO_MATH_INLINES
98 # define __NO_MATH_INLINES 1 /* for glibc */
101 float (*funcptr) (float) = floorf;
103 [[x = funcptr(x) + floorf(x);]])],
104 [gl_cv_func_floorf_libm="-lm"])
108 FLOORF_LIBM="$gl_cv_func_floorf_libm"