CREATE OR REPLACE PROCEDURE XX(C IN EMP.EMPNO%TYPE)
IS
PROCEDURE ZZ;
IS
BEGIN
INSERT INTO LOG_TAB(USER_ID,LOGDATA)
VALUES(USER,SYSDATE);
END ZZ;

BEGIN
DELETE FROM EMP
WHERE EMPNO=C;
ZZ;
END XX;

PROCEDURE ZZ;

it might be the semi-colun here

Remove the semi-colon after the text PROCEDURE ZZ; than it will be compile without any errors.

CREATE OR REPLACE PROCEDURE XX(C IN EMP.EMPNO%TYPE) IS
PROCEDURE ZZ
IS
BEGIN
INSERT INTO LOG_TAB(USER_ID,LOGDATA) VALUES(USER,SYSDATE);
END ZZ;

BEGIN
DELETE FROM EMP WHERE EMPNO=C;
ZZ;
END XX;