diff --git a/src/lcrypto.c b/src/lcrypto.c
index 48364d1..5a2ed78 100644
--- a/src/lcrypto.c
+++ b/src/lcrypto.c
@@ -1157,7 +1157,6 @@ static int pkey_to_pem(lua_State *L)
     struct evp_pkey_st *pkey_st = *pkey;
     int ret;
 
-    long len;
     BUF_MEM *buf;
     BIO *mem = BIO_new(BIO_s_mem());
 
@@ -1176,7 +1175,7 @@ static int pkey_to_pem(lua_State *L)
         goto error;
     }
 
-    len = BIO_get_mem_ptr(mem, &buf);
+    BIO_get_mem_ptr(mem, &buf);
     lua_pushlstring(L, buf->data, buf->length);
     ret = 1;
 
@@ -1217,7 +1216,7 @@ static int pkey_from_pem(lua_State *L)
     size_t ret;
 
     ret = BIO_puts(mem, key);
-    if (ret != strlen(key))
+    if (ret != (int)strlen(key))
     {
         goto error;
     }