diff --git a/roaring/roaring.go b/roaring/roaring.go
index 16e6159d7..266a9bfe3 100644
--- a/roaring/roaring.go
+++ b/roaring/roaring.go
@@ -3218,9 +3218,14 @@ func xorCompare(x *xorstm) (r1 interval16, has_data bool) {
 			r1 = interval16{start: x.va.start, last: x.vb.start - 1}
 			has_data = true
 		}
-		x.va.start = x.vb.last + 1
-		if x.va.start > x.va.last {
+		if x.vb.last == 65535 {
 			x.va_valid = false
+
+		} else {
+			x.va.start = x.vb.last + 1
+			if x.va.start > x.va.last {
+				x.va_valid = false
+			}
 		}
 
 	} else if x.vb.start <= x.va.start && x.vb.last >= x.va.last { //va inside
@@ -3230,26 +3235,39 @@ func xorCompare(x *xorstm) (r1 interval16, has_data bool) {
 			has_data = true
 		}
 
-		x.vb.start = x.va.last + 1
-		if x.vb.start > x.vb.last {
+		if x.va.last == 65535 {
 			x.vb_valid = false
+		} else {
+			x.vb.start = x.va.last + 1
+			if x.vb.start > x.vb.last {
+				x.vb_valid = false
+			}
 		}
 
 	} else if x.va.start < x.vb.start && x.va.last <= x.vb.last { //va first overlap
 		x.va_valid = false
 		r1 = interval16{start: x.va.start, last: x.vb.start - 1}
 		has_data = true
-		x.vb.start = x.va.last + 1
-		if x.vb.start > x.vb.last {
+		if x.va.last == 65535 {
 			x.vb_valid = false
+		} else {
+			x.vb.start = x.va.last + 1
+			if x.vb.start > x.vb.last {
+				x.vb_valid = false
+			}
 		}
 	} else if x.vb.start < x.va.start && x.vb.last <= x.va.last { //vb first overlap
 		x.vb_valid = false
 		r1 = interval16{start: x.vb.start, last: x.va.start - 1}
 		has_data = true
-		x.va.start = x.vb.last + 1
-		if x.va.start > x.va.last {
+
+		if x.vb.last == 65535 {
 			x.va_valid = false
+		} else {
+			x.va.start = x.vb.last + 1
+			if x.va.start > x.va.last {
+				x.va_valid = false
+			}
 		}
 	}
 	return
diff --git a/roaring/roaring_internal_test.go b/roaring/roaring_internal_test.go
index 59db885e1..74dcc8992 100644
--- a/roaring/roaring_internal_test.go
+++ b/roaring/roaring_internal_test.go
@@ -1834,8 +1834,8 @@ func TestXorRunRun(t *testing.T) {
 		},
 		{
 			aruns: []interval16{{start: 65530, last: 65535}},
-			bruns: []interval16{{start: 65531, last: 65535}},
-			exp:   []interval16{{start: 65530, last: 65530}},
+			bruns: []interval16{{start: 65532, last: 65535}},
+			exp:   []interval16{{start: 65530, last: 65531}},
 		},
 	}
 	for i, test := range tests {