diff -uNr libXt-1.2.0/configure libXt-1.2.0.mod/configure
--- libXt-1.2.0/configure	2019-06-22 02:30:06.000000000 +0300
+++ libXt-1.2.0.mod/configure	2019-06-29 23:10:33.160835538 +0300
@@ -19231,56 +19231,6 @@
 fi
 
 
-# Check for flag to avoid builtin definitions - assumes unix is predefined,
-# which is not the best choice for supporting other OS'es, but covers most
-# of the ones we need for now.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if $RAWCPP requires -undef" >&5
-$as_echo_n "checking if $RAWCPP requires -undef... " >&6; }
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-Does cpp redefine unix ?
-_ACEOF
-if test `${RAWCPP} < conftest.$ac_ext | grep -c 'unix'` -eq 1 ; then
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-else
-	if test `${RAWCPP} -undef < conftest.$ac_ext | grep -c 'unix'` -eq 1 ; then
-		RAWCPPFLAGS=-undef
-		{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-	# under Cygwin unix is still defined even with -undef
-	elif test `${RAWCPP} -undef -ansi < conftest.$ac_ext | grep -c 'unix'` -eq 1 ; then
-		RAWCPPFLAGS="-undef -ansi"
-		{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes, with -ansi" >&5
-$as_echo "yes, with -ansi" >&6; }
-	else
-		as_fn_error $? "${RAWCPP} defines unix with or without -undef.  I don't know what to do." "$LINENO" 5
-	fi
-fi
-rm -f conftest.$ac_ext
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if $RAWCPP requires -traditional" >&5
-$as_echo_n "checking if $RAWCPP requires -traditional... " >&6; }
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-Does cpp preserve   "whitespace"?
-_ACEOF
-if test `${RAWCPP} < conftest.$ac_ext | grep -c 'preserve   \"'` -eq 1 ; then
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-else
-	if test `${RAWCPP} -traditional < conftest.$ac_ext | grep -c 'preserve   \"'` -eq 1 ; then
-		TRADITIONALCPPFLAGS="-traditional"
-		RAWCPPFLAGS="${RAWCPPFLAGS} -traditional"
-		{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-	else
-		as_fn_error $? "${RAWCPP} does not preserve whitespace with or without -traditional.  I don't know what to do." "$LINENO" 5
-	fi
-fi
-rm -f conftest.$ac_ext
-
-