diff --git a/src/crypto/sha512/sha512block_generic.go b/src/crypto/sha512/sha512block_generic.go
index 08f2e07178..3eabd2c7c0 100644
--- a/src/crypto/sha512/sha512block_generic.go
+++ b/src/crypto/sha512/sha512block_generic.go
@@ -6,4 +6,6 @@
 
 package sha512
 
-var block = blockGeneric
+func block(dig *digest, p []byte) {
+	blockGeneric(dig, p)
+}