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commented
2 months ago This issue is not meant to be used for technical discussion. There is a Zulip stream for that. Use this issue to leave procedural comments, such as volunteering to review, indicating that you second the proposal (or third, etc), or raising a concern that you would like to be addressed.
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cc @rust-lang/compiler @rust-lang/compiler-contributors
saethlin
apiraino
Proposal
Context
See https://github.com/rust-lang/rust/issues/130375:
Some of our ui/codegen/assembly tests need to be built for a different target (i.e. cross-compilation scenario). There usually isn't a sysroot immediately available for the designated target nor is it trivial or cheap to build a sysroot for the target (especially as we have many targets). Fortunately, some of these tests don't need a full
-Z build-stdor sysroot for the target, they only need stubs for core/std prelude items. However, currently the tests don't have a good way to share the stubs, causing test writers to need to copy/paste or reinvent the core/std prelude stubs every time.EDIT: built not run
Proposed solution
As discussed in #130375, we can introduce a prototype implementation of
minicoreauxiliary test helper.minicorewould contain stub definitions of std/core prelude items intended for consumption by tests that want the typical prelude items likeCopyorResultin cross-compilation scenarios, but don't want nor need full-Z build-std(e.g.tests/ui/abi/compatibility.rs).The
minicoreauxiliary would be a single source filetests/auxiliary/minicore.rs. The path to this auxiliary is made avaiable from bootstrap to compiletest via the--minicore-pathcompiletest flag. Theminicoreauxiliary is then built when request via//@ use-minicorecompiletest directives, for each test revision for the given target (this distinction is important for when host != target in cross-compilation scenario).I have a prototype implementation and how a test (
tests/ui/abi/compatibility) looks with the minicore prelude and//@ use-minicoreat https://github.com/rust-lang/rust/pull/130693.Currently only ui/codegen/assembly test modes are intended to be supported.
Mentors or Reviewers
Anyone who is somewhat familiar with compiletest and our ui/codegen/assembly test suites.
@jieyouxu (myself) is happy to review any PRs that fix/improves this feature if this seems reasonable/desirable (I obviously can't approve my own prototype PR).
Process
The main points of the Major Change Process are as follows:
@rustbot second.-C flag, then full team check-off is required.@rfcbot fcp mergeon either the MCP or the PR.You can read more about Major Change Proposals on forge.
Comments
This issue is not meant to be used for technical discussion. There is a Zulip stream for that. Use this issue to leave procedural comments, such as volunteering to review, indicating that you second the proposal (or third, etc), or raising a concern that you would like to be addressed.