hi, came across this in website *https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html* <https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html> ............................................................................................................. -fprofile-use -fprofile-use=*path* Enable profile feedback-directed optimizations, and the following optimizations, *many of which are generally profitable only with profile feedback available: * -fbranch-probabilities -fprofile-values -funroll-loops -fpeel-loops -ftracer -fvpt -finline-functions -fipa-cp -fipa-cp-clone -fipa-bit-cp -fpredictive-commoning -fsplit-loops -funswitch-loops -fgcse-after-reload -ftree-loop-vectorize -ftree-slp-vectorize -fvect-cost-model=dynamic -ftree-loop-distribute-patterns -fprofile-reorder-functions ......................................................................................................... O3 optimization uses most of these flags. Since it has been mentioned as above I assumed that some optimization flags specified here cannot function without profile info. Can you please clarify whether the flags mentioned above can function without using profile information by just specifying O3? Thank you -- P.Ezhil, Asst Prof, L.N GOVERNMENT COLLEGE, PONNERI - 601204
