3 ms·

This all depends on build scenario/configuration. -O3 - take all the time you need, -O2 and below - please don't regress the performance of the compiler - as a

• eru 6y ago
  Yes, exactly, it's a question of what you ask from the compiler. Not sure whether the -O2 and -O3 system is the exact right choice to communicate that. But any better system would also preserve the user's ability to make this trade-off. Though I don't think there's necessarily anything magic about -O2. They could conceivably also only protect -O0 and perhaps -O1. Or give finer grained control over the trade-offs.
  • rubber_duck 6y ago
    -O2 is often the only usable output level in some scenarios even during development so it's important to keep it usable in development iterations, -O3 is "I don't care about compile time"