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Comment by israrkhan | Hacker News Reader

Apple has been preparing itself for independence from underlying CPU arachitecture for a while. In WWDC 2015[1], they announced bitcode. All App submissions to AppStore are compiled to to bitcode. This allows Apple to re-optimize/re-compile your app binary in the future for newer hardware without the need to submit new version of your app to the store.

This allows Apple to switch to intel chip on iPhone, or switch to an ARM chip on MacOS.

[1] https://thenextweb.com/apple/2015/06/17/apples-biggest-devel...

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> This allows Apple to switch to intel chip on iPhone, or switch to an ARM chip on MacOS.

I think you're assuming way too much. Says Chris Lattner regarding Bitcode, "It's useful for very specific, low-level kinds of enhancements, but it isn't a panacea that makes everything magically portable." [1]

[1]: http://atp.fm/205-chris-lattner-interview-transcript/#bitcod...

I believe Lattner said there was interest in making a CPU architecture independent bitcode though. At least bitcode is part of the way.

Similar to how Bell Labs Inferno worked. The kernel to user space interface was a register based VM called Dis. The entirety of user space was written in Limbo, the predecessor to Go (Both designed by Rob Pike), which allowed the whole of userspace and thus the bulk of the OS to be completely CPU independant. A JIT kept things speedy and performance penalties were about 30%. So your entire OS stack was CPU independent which allows applications to be written on an X86 machine and then ran on an Arm box with zero recopilation. True write-once-run-anywhere.

I have it built on my raspberry pi B+, Linux 32bit chroot, and there is a prebuilt Windows image available that you unzip and run.

Pity people still propel horrible names of software we had since 60s... How can any outsider take us seriously?

I saw the light when I read the plan 9 intro. And Rob Pike was right, The operating system still maters. In fact, I'd say it's more important than ever in the age of towering software stacks. We live in the distributed internet age but are hamstrung by 60's OS design.

> This allows Apple to switch to intel chip on iPhone, or switch to an ARM chip on MacOS.

Not easily. It's optional on iOS [1], and doesn't support completely new (non-ARM) CPU architectures. On macOS, the feature doesn't exist at all.

[1]: https://help.apple.com/xcode/mac/current/#/devbbdc5ce4f

In theory an LLVM-based bitcode-like system could allow Apple to change CPUs and automatically recompile App Store binaries without developer intervention, but their current bitcode system does not support that.

I just checked the app store on my Mac. I have just 1 application installed from the app store: Xcode. Even then that's just because Apple makes me have it installed to have command line tools such as git.

I think it's safe to say that the vast majority of applications (Microsoft Office, games, browsers, text editors, IDEs, etc.) installed on Macs are sourced from places other than the app store.

You can get the command line tools without installing Xcode from the App Store by running the command: xcode-select --install

Well, there goes the only App Store application then.

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