-O
-O1 Optimize. Optimizing compilation takes somewhat more time, and a lot more memory for a large
function.
With -O, the compiler tries to reduce code size and execution time, without performing any
optimizations that take a great deal of compilation time.
-O turns on the following optimization flags: -fdefer-pop -fmerge-constants -fthread-jumps
-floop-optimize -fif-conversion -fif-conversion2 -fdelayed-branch -fguess-branch-probability
-fcprop-registers
-O also turns on -fomit-frame-pointer on machines where doing so does not interfere with debugging.
|