Some people care more about compiler speed than the correctness? I would love to meet these imaginary people that are fine with a compiler that is straight up broken. Emitting working code is the baseline, not some preference slider.
Let's pretend, for just a second, that the people who do, having been able to learn how to program, are not absolute fucking morons. Straight up broken is obviously not useful, so maybe the conclusions you've jumped to could use some reexamination.
You might have not run Gentoo. Most Gentooers will begrudgingly but eventually admit to cooking their own gonads when updating a laptop.
Anyway, please define: "correctness".