-# floor.m4 serial 4
-dnl Copyright (C) 2007, 2009, 2010 Free Software Foundation, Inc.
+# floor.m4 serial 8
+dnl Copyright (C) 2007, 2009-2014 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
AC_DEFUN([gl_FUNC_FLOOR],
[
+ m4_divert_text([DEFAULTS], [gl_floor_required=plain])
+ AC_REQUIRE([gl_MATH_H_DEFAULTS])
dnl Test whether floor() can be used without libm.
gl_FUNC_FLOOR_LIBS
if test "$FLOOR_LIBM" = "?"; then
FLOOR_LIBM=
fi
+ m4_ifdef([gl_FUNC_FLOOR_IEEE], [
+ if test $gl_floor_required = ieee && test $REPLACE_FLOOR = 0; then
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_CACHE_CHECK([whether floor works according to ISO C 99 with IEC 60559],
+ [gl_cv_func_floor_ieee],
+ [
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $FLOOR_LIBM"
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#ifndef __NO_MATH_INLINES
+# define __NO_MATH_INLINES 1 /* for glibc */
+#endif
+#include <math.h>
+]gl_DOUBLE_MINUS_ZERO_CODE[
+]gl_DOUBLE_SIGNBIT_CODE[
+static double dummy (double f) { return 0; }
+int main (int argc, char *argv[])
+{
+ double (*my_floor) (double) = argc ? floor : dummy;
+ /* Test whether floor (-0.0) is -0.0. */
+ if (signbitd (minus_zerod) && !signbitd (my_floor (minus_zerod)))
+ return 1;
+ return 0;
+}
+ ]])],
+ [gl_cv_func_floor_ieee=yes],
+ [gl_cv_func_floor_ieee=no],
+ [case "$host_os" in
+ # Guess yes on glibc systems.
+ *-gnu*) gl_cv_func_floor_ieee="guessing yes" ;;
+ # If we don't know, assume the worst.
+ *) gl_cv_func_floor_ieee="guessing no" ;;
+ esac
+ ])
+ LIBS="$save_LIBS"
+ ])
+ case "$gl_cv_func_floor_ieee" in
+ *yes) ;;
+ *) REPLACE_FLOOR=1 ;;
+ esac
+ fi
+ ])
+ if test $REPLACE_FLOOR = 1; then
+ dnl No libraries are needed to link lib/floor.c.
+ FLOOR_LIBM=
+ fi
AC_SUBST([FLOOR_LIBM])
])