I'm not sure if -64 is the right flag to use here (since arm64 is a 64 bit architecture too), maybe it would be better to use something more specific like -x86-64?

We're already using -64 and -32 in a lot of places to mean 32-bit and 64-bit x86. With that in mind, I think that we should continue to use -64 here for consistency.

However, I am not against adding an alternate flag that means the same thing, but has a clearer name. Perhaps even making that alternate the new default and deprecating -32 and -64 to eventually get removed in a few years or whatever.

With that in mind, I think that we should continue to use -64 here for consistency.

Makes sense, thanks.

However, I am not against adding an alternate flag that means the same thing, but has a clearer name.

Sounds good. Maybe we should deal with adding these in a separate PR/issue, because it looks like android ios is already using "i386" so we'll have to decide on consistent names for these.

Merging, and we can decide on the new flags in #1819.