clang with "-Ofast"; I really wonder, which other options are there?! And imho this just doesn't explain the 200% difference? And some other things which are b

clang with "-Ofast"; I really wonder, which other options are there?! And imho this just doesn't explain the 200% difference? And some other things which are bugging me: - can you only optimize for A53 on Android with the big.LITTLE-configurations (they do!)? - so they cross-compiled an AMD64-producing gcc 3.2 with Xcode 10 on MacOS-X for ARM? impressive.