diff --git a/TODO b/TODO
index f130a79f00616bcefa71f8b85899d8c2d94f5b55..88c32228e4774073a6400068ed944685e69bef71 100644
--- a/TODO
+++ b/TODO
@@ -19,6 +19,7 @@ Version 1.4.0:
 * Adapt remaining examples.
 * READMEs for examples.
 * Update documentation.
+* Check for data sizes when reading mapping.
 
 * SDO write access.
 * Wait for bus scanning, even when link is not up at ecrt_request_master().