Gcc manuals says " Not all optimizations are controlled 'directly' by a flag. Only optimizations that have a flag are listed." What does it mean? Any one please help me. ___________________________________________________________ What kind of emailer are you? Find out today - get a free analysis of your email personality. Take the quiz at the Yahoo! Mail Championship. http://uk.rd.yahoo.com/evt=44106/*http://mail.yahoo.net/uk