diff --git a/src/ssl.c b/src/ssl.c
index 023558212..16e917e79 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -16957,7 +16957,7 @@ WOLFSSL_EVP_PKEY* wolfSSL_X509_get_pubkey(WOLFSSL_X509* x509)
                 return WOLFSSL_FAILURE;
             }
             if (wolfSSL_BIO_write(bio, "    Signature Algorithm: ",
-                               XSTRLEN("    Signature Algorithm: ")) <= 0) {
+                          (int)XSTRLEN("    Signature Algorithm: ")) <= 0) {
                 return WOLFSSL_FAILURE;
             }
             sig = GetSigName(oid);