Build failure on Windows UWP target (aarch64-uwp-windows-msvc, x86_64-uwp-windows-msvc, i686-uwp-windows-msvc)

[Darkspirit]

Log: servo/servo#26005 (comment)

[Darkspirit]

x86_64-uwp-windows-msvc was successful.
aarch64 windows is missing in

ring/build.rs

Lines 230 to 242 in ddfa683

	const ASM_TARGETS: &[(&str, Option<&str>, &str)] = &[
	("x86_64", Some("ios"), "macosx"),
	("x86_64", Some("macos"), "macosx"),
	("x86_64", Some(WINDOWS), "nasm"),
	("x86_64", None, "elf"),
	("aarch64", Some("ios"), "ios64"),
	("aarch64", None, "linux64"),
	("x86", Some(WINDOWS), "win32n"),
	("x86", Some("ios"), "macosx"),
	("x86", None, "elf"),
	("arm", Some("ios"), "ios32"),
	("arm", None, "linux32"),
	];

.

[briansmith]

I'm happy to add this. I don't know how to do the test automation for UWP targets. Any ideas?

[Darkspirit]

This is what I've found about AppVeyor:
It seems Visual Studio 2017 or 2019 are required for arm64 support. The Rust project cross-compiles to aarch64-pc-windows-msvc for testing.
https://help.appveyor.com/discussions/questions/27382-arm64-support-in-the-default-image
https://github.com/rust-lang/rust/pull/54718/files
If desired, multiple images could be configured and arm64 be restricted to 2017:
https://github.com/erthink/libfpta/blob/2f866f265683d9b93eb032b822a1b8f6373a7f13/externals/t1ha/.appveyor.yml
This is how other projects configured AppVeyor with arm64:
https://github.com/search?q=arm64++filename%3A.appveyor.yml&type=Code&ref=advsearch&l=&l=

[briansmith]

It is fine to require VS 2017 or VS 2019 as the minimum version.

My question though is, after we built for, say, aarch64-uwp-windows-msvc, how do we actually run the tests on that plaform?

[briansmith]

My question though is, after we built for, say, aarch64-uwp-windows-msvc, how do we actually run the tests on that plaform?

...on a x86-64-pc-windows-msvc host.

[sumibi-yakitori]

Hello @briansmith
I want to build this library to the aarch64-uwp-windows-msvc target to use your library with HoloLens2.

I'm not familiar with Rust's build system.
Can't we use xargo test for automated tests?

[sumibi-yakitori]

I tried working on the aarch64-uwp-windows-msvc build,
but the yasm and nasm do not support Arm architecture...

[briansmith]

I tried working on the aarch64-uwp-windows-msvc build,
but the yasm and nasm do not support Arm architecture...

Right now, build.rs says "if we're on windows, use yasm or nasm." Instead it needs to say "if we're targetting x86-64 or x86-64 on windows, use yasm or nasm."

[briansmith]

I tried working on the aarch64-uwp-windows-msvc build,

Check out https://boringssl.googlesource.com/boringssl/+/bc7e2cb92d948de5f437e5eef2b1c3ad6281bb35. That's basically what we'll need to do to get it working, on top of adjusting the build system.

[sumibi-yakitori]

@briansmith
Thank you so much! I'll look into it.

[briansmith]

How are you even installing the rust toolchain for x86_64-uwp-windows-msvc, i686-uwp-windows-msvc, and aarch64-uwp-windows-msvc? I.e. what is the equivalent of rustup target add x86_64-uwp-windows-msvc that you are doing?

The code change is very small, but I can't even test it without being able to install the toolchain.

[sumibi-yakitori]

I couldn't install the aarch64-uwp-windows-msvc and i686-uwp-windows-msvc toolchains in my environment with rustup or cargo, so I'm using xargo to install it.

rustup default nightly
cargo install xargo
rustup component add rust-src
xargo update
xargo build --target aarch64-uwp-windows-msvc
xargo build --target i686-uwp-windows-msvc

The DLL built this way (without ring) is now functional under my HoloLen2(Arm64+UWP) and HoloLens1(x86+UWP) environments.

My xargo.toml

[dependencies.std]
features = ["panic_unwind", "std_detect_dlsym_getauxval", "std_detect_file_io"]