448aa30b5a
Update the standard library to Rust 2024
This updates the standard library to Rust 2024. This includes the following notable changes:
- Macros are updated to use new expression fragment specifiers. This PR includes a test to illustrate the changes, primarily allowing `const {...}` expressions now.
- Some tests show a change in MIR drop order. We do not believe this will be an observable change ([see zulip discussion](https://rust-lang.zulipchat.com/#narrow/channel/268952-edition/topic/standard.20library.20migration/near/500972873)).
Fixes https://github.com/rust-lang/rust/issues/133081
UI Tests
This folder contains rustc's
UI tests.
Test Directives (Headers)
Typically, a UI test will have some test directives / headers which are special comments that tell compiletest how to build and interpret a test.
As part of an ongoing effort to rewrite compiletest
(see https://github.com/rust-lang/compiler-team/issues/536), a major
change proposal to change legacy compiletest-style headers // <directive>
to ui_test-style headers
//@ <directive> was accepted (see
https://github.com/rust-lang/compiler-team/issues/512.
An example directive is ignore-test. In legacy compiletest style, the header
would be written as
// ignore-test
but in ui_test style, the header would be written as
//@ ignore-test
compiletest is changed to accept only //@ directives for UI tests
(currently), and will reject and report an error if it encounters any
comments // <content> that may be parsed as a legacy compiletest-style
test header. To fix this, you should migrate to the ui_test-style header
//@ <content>.