On Wed, Sep 28, 2022 at 4:32 PM Wei Liu <wei.liu@xxxxxxxxxx> wrote: > > I do wonder how many more things you will need to list here. As far as > I can tell there is also other avx512* flags for the x86_64 target. Yeah, there are a lot of target features, but they are not getting enabled. Eventually, a stable target spec alternative (e.g. all relevant target feature flags) should be available, and then we can know what the guaranteed behavior will be and thus decide better which flags to keep or not depending on how explicit we want to be with respect to that. For the moment I went for consistency with the line above, since that was enough to disable everything we needed, though as you may have noticed, 3dnow and mmx are not there, because I had to move them back to the target spec [1]. [1] https://github.com/Rust-for-Linux/linux/commit/c5eae3a6e69c63dc8d69f51f74f74b853831ec71 Cheers, Miguel