When using the target features
prefer-256-bit, the compiler throws the warning:
warning: unknown feature specified for `-Ctarget-feature`: `prefer-256-bit` | = note: it is still passed through to the codegen backend = note: consider filing a feature request
This is even though the features are listed in the
rustc --print=target-features list, and actually works. From this code, disabling
prefer-256-bit clearly works as avx-512 registers are used in the generated assembly.
The warning said to consider filing a feature request, so here I am. Hope this can be fixed.