Allow rustdoc to handle asm! of foreign architectures
This allows rustdoc to process code containing `asm!` for architectures other than the current one. Since this never reaches codegen, we just replace target-specific registers and register classes with a dummy one.
Fixes#82869
Fixes issue #82920
Even if an item does not change between compilation sessions, it may end
up with a different `DefId`, since inserting/deleting an item affects
the `DefId`s of all subsequent items. Therefore, we use a `DefPathHash`
in the incremental compilation system, which is stable in the face of
changes to unrelated items.
In particular, the query system will consider the inputs to a query to
be unchanged if any `DefId`s in the inputs have their `DefPathHash`es
unchanged. Queries are pure functions, so the query result should be
unchanged if the query inputs are unchanged.
Unfortunately, it's possible to inadvertantly make a query result
incorrectly change across compilations, by relying on the specific value
of a `DefId`. Specifically, if the query result is a slice that gets
sorted by `DefId`, the precise order will depend on how the `DefId`s got
assigned in a particular compilation session. If some definitions end up
with different `DefId`s (but the same `DefPathHash`es) in a subsequent
compilation session, we will end up re-computing a *different* value for
the query, even though the query system expects the result to unchanged
due to the unchanged inputs.
It turns out that we have been sorting the predicates computed during
`astconv` by their `DefId`. These predicates make their way into the
`super_predicates_that_define_assoc_type`, which ends up getting used to
compute the vtables of trait objects. This, re-ordering these predicates
between compilation sessions can lead to undefined behavior at runtime -
the query system will re-use code built with a *differently ordered*
vtable, resulting in the wrong method being invoked at runtime.
This PR avoids sorting by `DefId` in `astconv`, fixing the
miscompilation. However, it's possible that other instances of this
issue exist - they could also be easily introduced in the future.
To fully fix this issue, we should
1. Turn on `-Z incremental-verify-ich` by default. This will cause the
compiler to ICE whenver an 'unchanged' query result changes between
compilation sessions, instead of causing a miscompilation.
2. Remove the `Ord` impls for `CrateNum` and `DefId`. This will make it
difficult to introduce ICEs in the first place.
resolve: Reduce scope of `pub_use_of_private_extern_crate` deprecation lint
This lint was deny-by-default since July 2017, crater showed 7 uses on crates.io back then (https://github.com/rust-lang/rust/pull/42894#issuecomment-311921147).
Unfortunately, the construction `pub use foo as bar` where `foo` is `extern crate foo;` was used by an older version `bitflags`, so turning it into an error causes too many regressions.
So, this PR reduces the scope of the lint instead of turning it into a hard error, and only turns some more rarely used components of it into errors.
- Rename `broken_intra_doc_links` to `rustdoc::broken_intra_doc_links`
- Ensure that the old lint names still work and give deprecation errors
- Register lints even when running doctests
Otherwise, all `rustdoc::` lints would be ignored.
- Register all existing lints as removed
This unfortunately doesn't work with `register_renamed` because tool
lints have not yet been registered when rustc is running. For similar
reasons, `check_backwards_compat` doesn't work either. Call
`register_removed` directly instead.
- Fix fallout
+ Rustdoc lints for compiler/
+ Rustdoc lints for library/
Note that this does *not* suggest `rustdoc::broken_intra_doc_links` for
`rustdoc::intra_doc_link_resolution_failure`, since there was no time
when the latter was valid.
Add test to prevent src link regression
Fixes#80502.
This PR is simply about adding a test to prevent a regression.
cc `@bugadani` `@CraftSpider`
r? `@camelid`
Unfortunately, this can't currently be tested. The problem is that we
need the file to be compiled first to then be used as dependency, which
cannot be done currently unfortunately in the rustdoc test suites.
Example:
```rust
// name this file "foo.rs"
/// ```
/// let x = foo::foo();
/// ```
pub fn foo() {}
```
If you run `rustdoc --test foo.rs`, you'll get:
```
running 1 test
test foo.rs - foo (line 1) ... FAILED
failures:
---- foo.rs - foo (line 1) stdout ----
error[E0463]: can't find crate for `foo`
--> foo.rs:0:1
|
2 | extern crate foo;
| ^^^^^^^^^^^^^^^^^ can't find crate
```
If a test were possible, it would look something like
````rust
#![crate_name = "mod"]
#![crate_type = "lib"]
//! ```
//! // NOTE: requires that the literal string 'mod' appears in the doctest for
//! // the bug to appear
//! assert_eq!(1, 1);
//! ```
````
The angle brackets were not rendered, so code like this:
some_func: for<'a> fn(val: &'a i32) -> i32
would be rendered as:
some_func: fn'a(val: &'a i32) -> i32
However, rendering with angle brackets is still invalid syntax:
some_func: fn<'a>(val: &'a i32) -> i32
so now it renders correctly as:
some_func: for<'a> fn(val: &'a i32) -> i32
-----
However, note that this code:
some_trait: dyn for<'a> Trait<'a>
will still render as:
some_trait: dyn Trait<'a>
which is not invalid syntax, but is still unclear. Unfortunately I think
it's hard to fix that case because there isn't enough information in the
`rustdoc::clean::Type` that this code operates on. Perhaps that case can
be fixed in a later PR.
Fix rendering of stabilization version for trait implementors
Rustdoc compares an item's stabilization version with its parent's to not render it if they are the same. Here, the implementor was compared with itself, resulting in the stabilization version never getting shown.
This probably needs a test.
Fixes#80777.
r? `@jyn514`
Deprecate-in-future the constants superceded by RFC 2700
Successor to #78335, re-opened after addressing the issues tracked in #68490.
This PR makes use of the new ability to explicitly annotate an item as triggering the deprecated-in-future lint (via `rustc_deprecated(since="TBD"`, see #78381). We might call this *soft deprecation*; unlike with deprecation, users will *not* receive warnings when compiling code that uses these items *unless* they opt-in via `#[warn(deprecated_in_future)]`. Like deprecation, soft deprecation causes documentation to formally acknowledge that an item is marked for eventual deprecation (at a non-specific point in the future).
With this new ability, we can sidestep all debate about when or on what timeframe something ought to be deprecated; as long as we can agree that something ought to be deprecated, we can receive much of the benefits of deprecation with none of the drawbacks. For these items specifically, the libs team has already agreed that they should be deprecated (see https://github.com/rust-lang/rust/issues/68490#issuecomment-747022696).