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AX_C_ARITHMETIC_RSHIFT
Checks if the right shift operation is arithmetic.
This macro uses compile-time detection and so is cross-compile ready.
YAMAMOTO Kengo <yamaken AT bp.iij4u.or.jp>
2006-12-12
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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