--- configure.orig	2021-04-22 18:04:21 UTC
+++ configure
@@ -330,10 +330,10 @@ if [ z$NOX11 = z ]; then
 
 	XOK=0
 
-	XINCLUDE=-I/usr/X11R6/include
+	XINCLUDE=-I${LOCALBASE}/include
 	$CC $CFLAGS _test_x11.c -c -o _test_x11.o $XINCLUDE 2> /dev/null
 
-	XLIB="-L/usr/X11R6/lib -lX11 -Wl,-rpath,/usr/X11R6/lib"
+	XLIB="-L${LOCALBASE}/lib -lX11 -Wl,-rpath,${LOCALBASE}/lib"
 	$CC $CFLAGS _test_x11.o -o _test_x11 $XLIB 2> /dev/null
 
 	if [ -x _test_x11 ]; then
@@ -539,27 +539,6 @@ else
 	fi
 fi
 rm -f _testprog _testprog.error _testprog.stdout
-
-
-#  -O optimization for non-debug builds. Try -O and -O3.
-if [ ! z"$DEBUG" = zYES ]; then
-	printf "checking whether -O3 or -O can be used (non-DEBUG build)... "
-	$CC $CFLAGS -O _testprog.c -o _testprog 2> /dev/null
-	if [ -x _testprog ]; then
-		rm -f _testprog
-		$CC $CFLAGS -O3 _testprog.c -o _testprog 2> /dev/null
-		if [ -x _testprog ]; then
-			CFLAGS="-O3 $CFLAGS"
-			printf "yes, -O3\n"
-		else
-			CFLAGS="-O $CFLAGS"
-			printf "yes, -O\n"
-		fi
-	else
-		printf "no\n"
-	fi
-fi
-rm -f _testprog
 
 
 #  -fpeephole