Building 3rd-tier targets so Rustup/Cargo can use them?

I need to try building something against the UWP targets to see if I can get it working on an Xbox. For this, I'll need to build and install the UWP target which is tier 3.

Is it possible to build and install a tier 3 target such that Cargo installed via rustup finds it? I.e. so cargo build --target x86_64-uwp-msvc (or whatever the name is) works? Or do I need to build and use an entirely separate toolchain?

Thanks.

I haven't tried myself, but there are a couple of tools helpful for working with custom Rust builds. If you want to build stdlib:

or if you want to use a custom build of Rust and Cargo seamlessly with rustup:

1 Like

Thanks, I'll give that a shot. For some reason Google was failing me, so
I'm glad rustup link does what I want.

One thing I'm not entirely clear on after reading
https://wesleywiser.github.io/post/custom-rust-toolchain/:

It shows linking 2 stages. If I just want to cross-compile such that I
use the host compiler but the newly-built x86_64-uwp-windows-msvc as
--target, which of these do I build, and what do I specify the toolchain
name as? I'm not clear whether this builds something I have to reference
via rustup override or if I can just use it via the --target option.

I'd experiment myself, but the build is naturally taking a while, and
I've already had a few false starts before I got config.toml set up
correctly. :slight_smile: Hoping to figure out any remaining issues more quickly
and, should this actually work, figure out the quickest way to build and
link only what I need to build a UWP DLL in CI.

Thanks.

Toolchain name can be anything you want. It's only a human-readable nickname.

You only need to build stage1. Stage0 is for libstd only, and stage2 is for compiler releases. stage1 and 2 is the same thing, but built with different versions of Rust compiler. They don't affect what platforms are supported.

This topic was automatically closed 90 days after the last reply. We invite you to open a new topic if you have further questions or comments.