On Tue, 10 Nov 2020 at 04:14, Ezhil P via Gcc-help <gcc-help@xxxxxxxxxxx> wrote: > > hi, > Have a great day > In GCC does optimization levels O2 and O3 use profile information by > default without specifying -fprofile options explicitly? No. > Because O3 uses > flags like -fipa-cp-clone which actually require profile information. I don't think it requires it. It works better with profile info, but doesn't require it. > If so , where are the data files related to profile information stored for > reference? They're not, because profile info is not used unless enabled explicitly.
