diff --git a/lib/storage/tag_filters.go b/lib/storage/tag_filters.go
index 497fd78cef..4af54d8fff 100644
--- a/lib/storage/tag_filters.go
+++ b/lib/storage/tag_filters.go
@@ -592,13 +592,13 @@ func extractRegexpPrefix(b []byte) ([]byte, []byte) {
 	if re == emptyRegexp {
 		return nil, nil
 	}
-	if re.Op == syntax.OpLiteral && re.Flags & syntax.FoldCase == 0 {
+	if re.Op == syntax.OpLiteral && re.Flags&syntax.FoldCase == 0 {
 		return []byte(string(re.Rune)), nil
 	}
 	var prefix []byte
 	if re.Op == syntax.OpConcat {
 		sub0 := re.Sub[0]
-		if sub0.Op == syntax.OpLiteral && sub0.Flags & syntax.FoldCase == 0 {
+		if sub0.Op == syntax.OpLiteral && sub0.Flags&syntax.FoldCase == 0 {
 			prefix = []byte(string(sub0.Rune))
 			re.Sub = re.Sub[1:]
 			if len(re.Sub) == 0 {