mrustc: new port

[evanmiller]

Description

mrustc is an alternative Rust compiler suitable for bootstrapping Rust. The immediate motivation is to provide a basic Rust compiler on Snow Leopard, which isn't supported by the main rust port.

In the future mrustc might be used as a stage0 compiler for rust, but that's beyond the scope of this work.

mrustc requires a run-time C compiler. Since the system GCC on 10.6 cannot compile mrustc's generated C files (which use thread-local storage), I have patched things to use clang-mp-9.0 as the default run-time compiler on all platforms. This default can be overridden at run-time with CC. The choice of default compiler will be a good candidate for port variants in the future.

Tested through compiling and running a basic "Hello, world!" Rust program, so I think it's ready for others to play around with.

Type(s)

• bugfix
• enhancement
• security fix

Tested on

macOS 10.6.8
Xcode x.y

Verification

Have you

• followed our Commit Message Guidelines?
• squashed and minimized your commits?
• checked that there aren't other open pull requests for the same change?
• referenced existing tickets on Trac with full URL?
• checked your Portfile with port lint?
• tried existing tests with sudo port test?
• tried a full install with sudo port -vst install?
• tested basic functionality of all binary files?

[evanmiller]

Installing dependency (9 of 25) 'xz' with variants '' ... [FAIL]

Anyone know why this fails on CI?

[herbygillot]

Anyone know why this fails on CI?

I've triggered the CI jobs to re-run.

[evanmiller]

Updated the code and added a test target (which passes locally).

[mascguy]

@catap Kirill, you might be interested in this too!

[catap]

@mascguy thanks, it is interesting. I haven't got a time to finish 10.6 :) maybe someone else can do it.

@evanmiller FYI I've backported LLVM changes: https://reviews.llvm.org/D115250?id=392731 maybe you may suggest to use this patch at upstream of this tool

[evanmiller]

Updated the code and adopted @cjones051073's suggestions regarding the run-time compiler.

This build may fail due to some recent changes in mrustc, reported here: thepowersgang/mrustc#210

[evanmiller]

I have isolated and fixed the recent local build failures described in the linked issue.

Updated the code and Portfile to consolidate patches and have better GCC compatibility.

I have a slight preference to wait until thepowersgang/mrustc#192 is merged, but if CI passes this PR should be ready as-is.

[pmetzger]

@evanmiller Let us know when you want this committed.

[evanmiller]

@pmetzger Will do. Still working through a GCC-related issue over here: thepowersgang/mrustc#214

[evanmiller]

This is OK to commit; I will address any remaining issues as they are resolved upstream.