-# roundf.m4 serial 8
-dnl Copyright (C) 2007-2010 Free Software Foundation, Inc.
+# roundf.m4 serial 13
+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])
AC_CHECK_DECLS([roundf], , , [#include <math.h>])
if test "$ac_cv_have_decl_roundf" = yes; then
gl_CHECK_MATH_LIB([ROUNDF_LIBM], [x = roundf (x);])
- fi
- if test "$ac_cv_have_decl_roundf" = yes && test "$ROUNDF_LIBM" != missing; then
- dnl Test whether roundf() produces correct results. On mingw, for
- dnl x = 1/2 - 2^-25, the system's roundf() returns a wrong result.
- AC_REQUIRE([AC_PROG_CC])
- AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
- AC_CACHE_CHECK([whether roundf works], [gl_cv_func_roundf_works],
- [
- save_LIBS="$LIBS"
- LIBS="$LIBS $ROUNDF_LIBM"
- AC_RUN_IFELSE([AC_LANG_SOURCE([[
+ if test "$ROUNDF_LIBM" != missing; then
+ dnl Test whether roundf() produces correct results. On mingw, for
+ dnl x = 1/2 - 2^-25, the system's roundf() returns a wrong result.
+ AC_REQUIRE([AC_PROG_CC])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_CACHE_CHECK([whether roundf works], [gl_cv_func_roundf_works],
+ [
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $ROUNDF_LIBM"
+ AC_RUN_IFELSE([AC_LANG_SOURCE([[
#include <float.h>
#include <math.h>
int main()
volatile float x = 0.5f - 0.5f / TWO_MANT_DIG;
exit (x < 0.5f && roundf (x) != 0.0f);
}]])], [gl_cv_func_roundf_works=yes], [gl_cv_func_roundf_works=no],
- [case "$host_os" in
- mingw*) gl_cv_func_roundf_works="guessing no";;
- *) gl_cv_func_roundf_works="guessing yes";;
- esac
+ [case "$host_os" in
+ mingw*) gl_cv_func_roundf_works="guessing no";;
+ *) gl_cv_func_roundf_works="guessing yes";;
+ esac
+ ])
+ LIBS="$save_LIBS"
])
- LIBS="$save_LIBS"
- ])
- case "$gl_cv_func_roundf_works" in
- *no) ROUNDF_LIBM=missing ;;
- esac
+ case "$gl_cv_func_roundf_works" in
+ *no) ROUNDF_LIBM=missing ;;
+ esac
+ fi
+ if test "$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 $ROUNDF_LIBM"
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#ifndef __NO_MATH_INLINES
+# define __NO_MATH_INLINES 1 /* for glibc */
+#endif
+#include <math.h>
+]gl_FLOAT_MINUS_ZERO_CODE[
+]gl_FLOAT_SIGNBIT_CODE[
+static float dummy (float f) { return 0; }
+int main (int argc, char *argv[])
+{
+ float (*my_roundf) (float) = argc ? roundf : dummy;
+ int result = 0;
+ /* Test whether roundf (-0.0f) is -0.0f. */
+ if (signbitf (minus_zerof) && !signbitf (my_roundf (minus_zerof)))
+ result |= 1;
+ /* Test whether roundf (-0.3f) is -0.0f. */
+ if (signbitf (-0.3f) && !signbitf (my_roundf (-0.3f)))
+ result |= 2;
+ return result;
+}
+ ]])],
+ [gl_cv_func_roundf_ieee=yes],
+ [gl_cv_func_roundf_ieee=no],
+ [gl_cv_func_roundf_ieee="guessing no"])
+ LIBS="$save_LIBS"
+ ])
+ case "$gl_cv_func_roundf_ieee" in
+ *yes) ;;
+ *) REPLACE_ROUNDF=1 ;;
+ esac
+ fi
+ ])
+ else
+ HAVE_DECL_ROUNDF=0
fi
- if test "$ac_cv_have_decl_roundf" != yes || test "$ROUNDF_LIBM" = missing; then
- REPLACE_ROUNDF=1
- AC_LIBOBJ([roundf])
+ if test $HAVE_DECL_ROUNDF = 0 || test $REPLACE_ROUNDF = 1; then
+ dnl Find libraries needed to link lib/roundf.c.
AC_CHECK_DECLS([ceilf, floorf], , , [#include <math.h>])
if test "$ac_cv_have_decl_floorf" = yes \
&& test "$ac_cv_have_decl_ceilf" = yes; then