diff --git a/c_src/lmdb.c b/c_src/lmdb.c
index a366b40..c49035c 100644
--- a/c_src/lmdb.c
+++ b/c_src/lmdb.c
@@ -10671,6 +10671,7 @@ int mdb_set_relctx(MDB_txn *txn, MDB_dbi dbi, void *ctx)
 int ESECT
 mdb_env_get_maxkeysize(MDB_env *env)
 {
+	env = env;
 	return ENV_MAXKEY(env);
 }
 
diff --git a/c_src/lmdb_nif.c b/c_src/lmdb_nif.c
index f1a0c50..67cada3 100644
--- a/c_src/lmdb_nif.c
+++ b/c_src/lmdb_nif.c
@@ -102,7 +102,7 @@ static ERL_NIF_TERM ATOM_TXN_NOT_STARTED;
 static ERL_NIF_TERM
 __strerror_term(ErlNifEnv* env, int err)
 {
-    ERL_NIF_TERM term;
+    ERL_NIF_TERM term = 0;
 
     if (err < MDB_LAST_ERRCODE && err > MDB_KEYEXIST) {
 	switch (err) {
diff --git a/tools/update-mdb b/tools/update-mdb
new file mode 100755
index 0000000..d3e32ec
--- /dev/null
+++ b/tools/update-mdb
@@ -0,0 +1,6 @@
+#!/bin/bash
+
+for file in lmdb.h mdb.c midl.h midl.c; do
+  curl -O https://raw.githubusercontent.com/LMDB/lmdb/mdb.master/libraries/liblmdb/$file
+done
+