-# roundl.m4 serial 4
-dnl Copyright (C) 2007 Free Software Foundation, Inc.
+# roundl.m4 serial 11
+dnl Copyright (C) 2007, 2009-2011 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_ROUNDL],
[
+ m4_divert_text([DEFAULTS], [gl_roundl_required=plain])
AC_REQUIRE([gl_MATH_H_DEFAULTS])
dnl Persuade glibc <math.h> to declare roundl().
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
AC_CHECK_DECLS([roundl], , , [#include <math.h>])
if test "$ac_cv_have_decl_roundl" = yes; then
gl_CHECK_MATH_LIB([ROUNDL_LIBM], [x = roundl (x);])
+ if test "$ROUNDL_LIBM" = missing; then
+ REPLACE_ROUNDL=1
+ fi
+ m4_ifdef([gl_FUNC_ROUNDL_IEEE], [
+ if test $gl_roundl_required = ieee && test $REPLACE_ROUNDL = 0; then
+ AC_CACHE_CHECK([whether roundl works according to ISO C 99 with IEC 60559],
+ [gl_cv_func_roundl_ieee],
+ [
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $ROUNDL_LIBM"
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#ifndef __NO_MATH_INLINES
+# define __NO_MATH_INLINES 1 /* for glibc */
+#endif
+#include <math.h>
+]gl_LONG_DOUBLE_MINUS_ZERO_CODE[
+]gl_LONG_DOUBLE_SIGNBIT_CODE[
+static long double dummy (long double f) { return 0; }
+int main (int argc, char *argv[])
+{
+ long double (*my_roundl) (long double) = argc ? roundl : dummy;
+ int result = 0;
+ /* Test whether roundl (-0.0L) is -0.0L. */
+ if (signbitl (minus_zerol) && !signbitl (my_roundl (minus_zerol)))
+ result |= 1;
+ /* Test whether roundl (-0.3L) is -0.0L. */
+ if (signbitl (-0.3L) && !signbitl (my_roundl (-0.3L)))
+ result |= 2;
+ return result;
+}
+ ]])],
+ [gl_cv_func_roundl_ieee=yes],
+ [gl_cv_func_roundl_ieee=no],
+ [gl_cv_func_roundl_ieee="guessing no"])
+ LIBS="$save_LIBS"
+ ])
+ case "$gl_cv_func_roundl_ieee" in
+ *yes) ;;
+ *) REPLACE_ROUNDL=1 ;;
+ esac
+ fi
+ ])
+ else
+ HAVE_DECL_ROUNDL=0
fi
- if test "$ac_cv_have_decl_roundl" != yes || test "$ROUNDL_LIBM" = missing; then
- REPLACE_ROUNDL=1
- AC_LIBOBJ([roundl])
+ if test $HAVE_DECL_ROUNDL = 0 || test $REPLACE_ROUNDL = 1; then
+ dnl Find libraries needed to link lib/roundl.c.
AC_CHECK_DECLS([ceill, floorl], , , [#include <math.h>])
if test "$ac_cv_have_decl_floorl" = yes \
&& test "$ac_cv_have_decl_ceill" = yes; then
gl_FUNC_FLOORL_LIBS
gl_FUNC_CEILL_LIBS
if test "$FLOORL_LIBM" != '?' && test "$CEILL_LIBM" != '?'; then
- AC_DEFINE([HAVE_FLOORL_AND_CEILL], 1,
+ AC_DEFINE([HAVE_FLOORL_AND_CEILL], [1],
[Define if the both the floorl() and ceill() functions exist.])
- ROUNDL_LIBM="$FLOORL_LIBM $CEILL_LIBM"
+ ROUNDL_LIBM=
+ dnl Append $FLOORL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
+ case " $ROUNDL_LIBM " in
+ *" $FLOORL_LIBM "*) ;;
+ *) ROUNDL_LIBM="$ROUNDL_LIBM $FLOORL_LIBM" ;;
+ esac
+ dnl Append $CEILL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
+ case " $ROUNDL_LIBM " in
+ *" $CEILL_LIBM "*) ;;
+ *) ROUNDL_LIBM="$ROUNDL_LIBM $CEILL_LIBM" ;;
+ esac
else
ROUNDL_LIBM=
fi