SELECT  'ALTER ' || OBJECT_TYPE || ' ' || OWNER || '.' || OBJECT_NAME || ' COMPILE;'
INTO    V_AL_QUERY
FROM    SYS.ALL_OBJECTS;
EXECUTE IMMEDIATE V_AL_QUERY;

DECLARE
   v_al_query   VARCHAR2 (2000);
   sql_stmt		varchar2(2000);
BEGIN
   SELECT    'ALTER '
          || object_type
          || ' '
          || owner
          || '.'
          || object_name
          || ' COMPILE;'
     INTO v_al_query
     FROM SYS.all_objects;

  EXECUTE IMMEDIATE V_AL_QUERY;
END;

ORA-01422: exact fetch returns more than requested number of rows

.....
FOR OBJ IN OBJECTS LOOP
            V_OBJECT_NAME := OBJ.OBJECT_NAME;
            SELECT  'ALTER ' || OBJECT_TYPE || ' ' || OWNER || '.' || OBJECT_NAME || ' COMPILE;'
            INTO    V_AL_QUERY
            FROM    SYS.ALL_OBJECTS
            WHERE   STATUS = 'INVALID'
            AND     OBJECT_NAME = V_OBJECT_NAME
            AND     OBJECT_TYPE IN ('PACKAGE','FUNCTION','PROCEDURE');
            EXECUTE IMMEDIATE V_AL_QUERY;
    END LOOP;--END OBJECTS LOOP
....
EXCEPTION WHEN OTHERS THEN
        DBMS_OUTPUT.PUT_LINE('Error...'||sqlerrm||'----'||sqlcode);

ORA-00911: invalid character-----911

dbms_utility.exec_ddl_statement(ALTER STATEMENT);

Error...ORA-01031: insufficient privileges-----1031