diff --git a/lsh512/test_amd64_test.go b/lsh512/test_amd64_test.go
index f3ca822..d03077e 100644
--- a/lsh512/test_amd64_test.go
+++ b/lsh512/test_amd64_test.go
@@ -1,3 +1,5 @@
+//go:build amd64 && gc && !purego
+
 package lsh512
 
 import (