diff --git a/wolfssl/wolfcrypt/sha512.h b/wolfssl/wolfcrypt/sha512.h
index 1b4813246..958e7688b 100644
--- a/wolfssl/wolfcrypt/sha512.h
+++ b/wolfssl/wolfcrypt/sha512.h
@@ -142,7 +142,8 @@ typedef struct wc_Sha512 {
 #endif /* HAVE_FIPS */
 
 #if defined(WOLFSSL_ARMASM) && defined(__aarch64__)
-int Transform_Sha512_Len(wc_Sha512* sha512, const byte* data, word32 len);
+WOLFSSL_LOCAL int Transform_Sha512_Len(wc_Sha512* sha512, const byte* data,
+                                       word32 len);
 #endif
 
 #ifdef WOLFSSL_SHA512