[ambrop7]

> -march=native and -mtune=broadwell tell the compiler to optimize for your architecture. One would think given the compiler documentation that march implies mtune, but this is apparently not the case.

That sounds like a bug to me which should be reported.

[saagarjha]

There's a thread discussing that topic: https://lemire.me/blog/2018/07/25/it-is-more-complicated-tha...