diff -up ./libraries/liblmdb/midl.c.fix ./libraries/liblmdb/midl.c

--- ./libraries/liblmdb/midl.c.fix	2019-06-19 11:10:07.791337785 +0200

+++ ./libraries/liblmdb/midl.c	2019-06-19 11:16:04.005166705 +0200

@@ -120,9 +120,15 @@ void mdb_midl_free(MDB_IDL ids)

 void mdb_midl_shrink( MDB_IDL *idp )

 {

 	MDB_IDL ids = *idp;

-	if (*(--ids) > MDB_IDL_UM_MAX &&

-		(ids = realloc(ids, (MDB_IDL_UM_MAX+2) * sizeof(MDB_ID))))

+  MDB_IDL res = NULL;

+	if (*(--ids) > MDB_IDL_UM_MAX)

 	{

+    res = realloc(ids, (MDB_IDL_UM_MAX+2) * sizeof(MDB_ID));

+    if (res)

+      ids = res;

+    else

+      return;

+

 		*ids++ = MDB_IDL_UM_MAX;

 		*idp = ids;

 	}

@@ -131,10 +137,13 @@ void mdb_midl_shrink( MDB_IDL *idp )

 static int mdb_midl_grow( MDB_IDL *idp, int num )

 {

 	MDB_IDL idn = *idp-1;

+  MDB_IDL res = NULL;

 	/* grow it */

-	idn = realloc(idn, (*idn + num + 2) * sizeof(MDB_ID));

-	if (!idn)

+	res = realloc(idn, (*idn + num + 2) * sizeof(MDB_ID));

+	if (!res)

 		return ENOMEM;

+  else

+    idn = res;

 	*idn++ += num;

 	*idp = idn;

 	return 0;