x/website: go.dev/doc/install links to the darwin/amd64 installer for Apple Silicon users

[hyangah]

From @dmitshur's comment in #47578 (comment) (thanks!)

To my knowledge, likely out of device fingerprinting concerns, browsers don't officially expose the underlying system architecture, so web pages typically look the same regardless of whether the user is visiting from a macOS device with an Intel or Apple CPU.

I'm aware there are some workarounds, like getting the device GPU vendor name and checking for a known substring that M1 devices have. An example of that being used is the VLC home page, https://www.videolan.org/, which changes its default download link using that heuristic.

So, I'm not sure that we should try to add automatic detection. If we make both downloads Featured, they should be equally visible and hopefully easier to pick the intended one.

I think detecting the underlying system may be difficult. Then, I think we should investigate alternatives

• Offer "Universal" as the default, but also provide "Intel Chip" and "Apple Silicon" options.
• Present both options for MacOS users: Either drop-down menu or two different download block. If we take this route, add first-time go user-friendly description to refer to each architecture (I rarely see darwin-arm64 or darwin-amd64 outside the go community)

[Deleplace]

Does "Universal" already exist, or are there plans to add "Universal" to https://go.dev/dl/ ?

[hyangah]

@Deleplace There is currently no universal version. I expect that will involve more work from the release team's side, and I am not aware of any plan. I added this as a possibility :-) And another consideration is the potential binary size.

[cespare]

To put a finer point on it: when a Apple Silicon mac user visits the download page, they are presented with this:

and that big download button is the wrong link.

They will probably install that package and everything will seem to work, because the emulation is very good. The programs they compile will be amd64 binaries and will run a little slower because they are running under Rosetta. They may only become aware that there is an issue when some deeper issue exposes the amd64/arm64 mismatch.

(This keeps happening at our company.)

I suspect that quite a large fraction of Apple Silicon Go users are using amd64 toolchains today.

I really think this needs fixing. For now, we can just have two download buttons to force the user to pick the appropriate one.

It also seems like the macOS installer should warn the user if they are installing the amd64 toolchain on an Apple Silicon machine.

[cespare]

I filed #59010 for making the amd64 installer complain if run on Apple Silicon.