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# ===========================================================================
# http://www.nongnu.org/autoconf-archive/ax_c_arithmetic_rshift.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_C_ARITHMETIC_RSHIFT
#
# DESCRIPTION
#
# Checks if the right shift operation is arithmetic.
#
# This macro uses compile-time detection and so is cross-compile ready.
#
# LICENSE
#
# Copyright (c) 2008 YAMAMOTO Kengo <yamaken AT bp.iij4u.or.jp>
#
# Copying and distribution of this file, with or without modification, are
# permitted in any medium without royalty provided the copyright notice
# and this notice are preserved.
AC_DEFUN([AX_C_ARITHMETIC_RSHIFT], [
AC_CACHE_CHECK([whether right shift operation is arithmetic],
[ax_cv_c_arithmetic_rshift],
[AC_COMPILE_IFELSE([[int dummy[((-1 >> 1) < 0) ? 1 : -1];]],
[ax_cv_c_arithmetic_rshift=yes],
[ax_cv_c_arithmetic_rshift=no])])
if test "x$ax_cv_c_arithmetic_rshift" = xyes; then
AC_DEFINE([HAVE_ARITHMETIC_RSHIFT], [1],
[Define to 1 if the right shift operation is arithmetic.])
fi
])
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