-# roundf.m4 serial 9
-dnl Copyright (C) 2007-2010 Free Software Foundation, Inc.
+# roundf.m4 serial 11
+dnl Copyright (C) 2007-2011 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_ROUNDF],
[
+ m4_divert_text([DEFAULTS], [gl_roundf_required=plain])
AC_REQUIRE([gl_MATH_H_DEFAULTS])
dnl Persuade glibc <math.h> to declare roundf().
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
if test "$ROUNDF_LIBM" = missing; then
REPLACE_ROUNDF=1
fi
+ m4_ifdef([gl_FUNC_ROUNDF_IEEE], [
+ if test $gl_roundf_required = ieee && test $REPLACE_ROUNDF = 0; then
+ AC_CACHE_CHECK([whether roundf works according to ISO C 99 with IEC 60559],
+ [gl_cv_func_roundf_ieee],
+ [
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $ROUNDF_LIBM"
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#ifndef __NO_MATH_INLINES
+# define __NO_MATH_INLINES 1 /* for glibc */
+#endif
+#include <math.h>
+]gl_FLOAT_MINUS_ZERO_CODE[
+]gl_FLOAT_SIGNBIT_CODE[
+int main()
+{
+ /* Test whether roundf (-0.0f) is -0.0f. */
+ if (signbitf (minus_zerof) && !signbitf (roundf (minus_zerof)))
+ return 1;
+ return 0;
+}
+ ]])],
+ [gl_cv_func_roundf_ieee=yes],
+ [gl_cv_func_roundf_ieee=no],
+ [gl_cv_func_roundf_ieee="guessing no"])
+ LIBS="$save_LIBS"
+ ])
+ case "$gl_cv_func_roundf_ieee" in
+ *yes) ;;
+ *) REPLACE_ROUNDF=1 ;;
+ esac
+ fi
+ ])
else
HAVE_DECL_ROUNDF=0
fi
if test $HAVE_DECL_ROUNDF = 0 || test $REPLACE_ROUNDF = 1; then
- AC_LIBOBJ([roundf])
+ dnl Find libraries needed to link lib/roundf.c.
AC_CHECK_DECLS([ceilf, floorf], , , [#include <math.h>])
if test "$ac_cv_have_decl_floorf" = yes \
&& test "$ac_cv_have_decl_ceilf" = yes; then