Merge pull request #21537 from lnicola/sync-from-rust

minor: Sync from downstream

Author: lnicola

src/debuginfo/lldb-visualizers.md

@@ -2,7 +2,7 @@
 
 > NOTE: LLDB's C++<->Python FFI expects a version of python designated at the time LLDB was
 >compiled. LLDB is careful to correspond this version to the minimum in typical Linux and macOS
->distributions, but on Windows there is no easy solution. If you recieve an import error regarding
+>distributions, but on Windows there is no easy solution. If you receive an import error regarding
 >`_lldb` not existing, a mismatched Python version is likely the cause.
 >
 > LLDB is considering solutions this issue. For updates, see

src/tests/compiletest.md

@@ -311,14 +311,20 @@ For example, `./x test tests/debuginfo -- --debugger gdb` will only test GDB com
 
 ### Codegen tests
 
-The tests in [`tests/codegen-llvm`] test LLVM code generation. They compile the test
-with the `--emit=llvm-ir` flag to emit LLVM IR. They then run the LLVM
+The tests in [`tests/codegen-llvm`] test LLVM code generation. They compile the
+test with the `--emit=llvm-ir` flag to emit LLVM IR. They then run the LLVM
 [FileCheck] tool. The test is annotated with various `// CHECK` comments to
 check the generated code. See the [FileCheck] documentation for a tutorial and
 more information.
 
 See also the [assembly tests](#assembly-tests) for a similar set of tests.
 
+By default, codegen tests will have `//@ needs-target-std` *implied* (that the
+target needs to support std), *unless* the `#![no_std]`/`#![no_core]` attribute
+was specified in the test source. You can override this behavior and explicitly
+write `//@ needs-target-std` to only run the test when target supports std, even
+if the test is `#![no_std]`/`#![no_core]`.
+
 If you need to work with `#![no_std]` cross-compiling tests, consult the
 [`minicore` test auxiliary](./minicore.md) chapter.
 
@@ -665,7 +671,9 @@ to link to the extern crate to make the crate be available as an extern prelude.
 That allows you to specify the additional syntax of the `--extern` flag, such as
 renaming a dependency. For example, `//@ aux-crate:foo=bar.rs` will compile
 `auxiliary/bar.rs` and make it available under then name `foo` within the test.
-This is similar to how Cargo does dependency renaming.
+This is similar to how Cargo does dependency renaming. It is also possible to
+specify [`--extern` modifiers](https://github.com/rust-lang/rust/issues/98405).
+For example, `//@ aux-crate:noprelude:foo=bar.rs`.
 
 `aux-bin` is similar to `aux-build` but will build a binary instead of a
 library. The binary will be available in `auxiliary/bin` relative to the working

src/tests/directives.md

@@ -53,14 +53,14 @@ Directives can generally be found by browsing the
 
 See [Building auxiliary crates](compiletest.html#building-auxiliary-crates)
 
-| Directive             | Explanation                                                                                           | Supported test suites                  | Possible values                               |
-|-----------------------|-------------------------------------------------------------------------------------------------------|----------------------------------------|-----------------------------------------------|
-| `aux-bin`             | Build a aux binary, made available in `auxiliary/bin` relative to test directory                      | All except `run-make`/`run-make-cargo` | Path to auxiliary `.rs` file                  |
-| `aux-build`           | Build a separate crate from the named source file                                                     | All except `run-make`/`run-make-cargo` | Path to auxiliary `.rs` file                  |
-| `aux-crate`           | Like `aux-build` but makes available as extern prelude                                                | All except `run-make`/`run-make-cargo` | `<extern_prelude_name>=<path/to/aux/file.rs>` |
-| `aux-codegen-backend` | Similar to `aux-build` but pass the compiled dylib to `-Zcodegen-backend` when building the main file | `ui-fulldeps`                          | Path to codegen backend file                  |
-| `proc-macro`          | Similar to `aux-build`, but for aux forces host and don't use `-Cprefer-dynamic`[^pm].                | All except `run-make`/`run-make-cargo` | Path to auxiliary proc-macro `.rs` file       |
-| `build-aux-docs`      | Build docs for auxiliaries as well.  Note that this only works with `aux-build`, not `aux-crate`.     | All except `run-make`/`run-make-cargo` | N/A                                           |
+| Directive             | Explanation                                                                                           | Supported test suites                  | Possible values                                                    |
+|-----------------------|-------------------------------------------------------------------------------------------------------|----------------------------------------|--------------------------------------------------------------------|
+| `aux-bin`             | Build a aux binary, made available in `auxiliary/bin` relative to test directory                      | All except `run-make`/`run-make-cargo` | Path to auxiliary `.rs` file                                       |
+| `aux-build`           | Build a separate crate from the named source file                                                     | All except `run-make`/`run-make-cargo` | Path to auxiliary `.rs` file                                       |
+| `aux-crate`           | Like `aux-build` but makes available as extern prelude                                                | All except `run-make`/`run-make-cargo` | `[<extern_modifiers>:]<extern_prelude_name>=<path/to/aux/file.rs>` |
+| `aux-codegen-backend` | Similar to `aux-build` but pass the compiled dylib to `-Zcodegen-backend` when building the main file | `ui-fulldeps`                          | Path to codegen backend file                                       |
+| `proc-macro`          | Similar to `aux-build`, but for aux forces host and don't use `-Cprefer-dynamic`[^pm].                | All except `run-make`/`run-make-cargo` | Path to auxiliary proc-macro `.rs` file                            |
+| `build-aux-docs`      | Build docs for auxiliaries as well.  Note that this only works with `aux-build`, not `aux-crate`.     | All except `run-make`/`run-make-cargo` | N/A                                                                |
 
 [^pm]: please see the [Auxiliary proc-macro section](compiletest.html#auxiliary-proc-macro) in the compiletest chapter for specifics.
 
@@ -200,6 +200,8 @@ The following directives will check rustc build settings and target settings:
   on `wasm32-unknown-unknown` target because the target does not support the
   `proc-macro` crate type.
 - `needs-target-std` — ignores if target platform does not have std support.
+  - See also [`#![no_std]`/`#![no_core]` and implied `needs-target-std` for
+    codegen tests](./compiletest.md#codegen-tests).
 - `ignore-backends` — ignores the listed backends, separated by whitespace characters.
   Please note
   that this directive can be overriden with the `--bypass-ignore-backends=[BACKEND]` command line