diff --git a/src/interfaces/ecpg/ecpglib/misc.c b/src/interfaces/ecpg/ecpglib/misc.c
index 02338a41ea..6039837d25 100644
--- a/src/interfaces/ecpg/ecpglib/misc.c
+++ b/src/interfaces/ecpg/ecpglib/misc.c
@@ -432,7 +432,7 @@ ECPGis_noind_null(enum ECPGttype type, const void *ptr)
 				return true;
 			break;
 		case ECPGt_bytea:
-			if (((struct ECPGgeneric_bytea *) ptr)->len == 0)
+			if (((const struct ECPGgeneric_bytea *) ptr)->len == 0)
 				return true;
 			break;
 		case ECPGt_decimal: