Search notes:

PLS-00215: String length constraints must be in range (1 .. 32767)

A variable that is declared to be a varchar2 needs also to have the maximum length, for example varname varchar2(20). If this length is not present (varname varchar2), the PL/SQL compiler will throw the error PLS-00215: String length constraints must be in range (1 .. 32767).

Note, a function or procedure parameter must not have such a maximum length.

create or replace procedure tq84_pls_00215(txt varchar2) -- << This is ok
   authid definer
as
   txt_out varchar2;                                     -- << This throws PLS-00215: String length constraints must be in range (1 .. 32767)
begin
   txt_out := upper(txt);
   dbms_output.put_line(txt);
end tq84_pls_00215;
/

PLS-00215: String length constraints must be in range (1 .. 32767)

See also