diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index 028013f..1bec949 100644
--- a/src/pl/plpgsql/src/pl_comp.c
+++ b/src/pl/plpgsql/src/pl_comp.c
@@ -424,10 +424,6 @@ do_compile(FunctionCallInfo fcinfo,
 				if (argvariable->dtype == PLPGSQL_DTYPE_VAR)
 				{
 					argitemtype = PLPGSQL_NSTYPE_VAR;
-					/* input argument vars are forced to be CONSTANT */
-					if (argmode == PROARGMODE_IN ||
-						argmode == PROARGMODE_VARIADIC)
-						((PLpgSQL_var *) argvariable)->isconst = true;
 				}
 				else
 				{