Reorder description for snippets in rustdoc documentation
The example code snippets for the `no_run` and `compile_fail` attributes in the rustdoc documentation were followed by the description for the wrong attribute. This patch reorders the descriptions to match the code snippets.
Turn deprecation lint `legacy_imports` into a hard error
Closes https://github.com/rust-lang/rust/issues/38260
The lint was introduced in Dec 2016, then made deny-by-default in Jun 2017 when crater run found 0 regressions caused by it.
This lint requires some not entirely trivial amount of import resolution logic that (surprisingly or not) interacts with `feature(use_extern_macros)` (https://github.com/rust-lang/rust/issues/35896), so it would be desirable to remove it before stabilizing `use_extern_macros`.
In particular, this PR fixes the failing example in https://github.com/rust-lang/rust/issues/50725 (but not the whole issue, `use std::panic::{self}` still can cause other undesirable errors when `use_extern_macros` is enabled).
The example code snippets for the `no_run` and `compile_fail` attributes
in the rustdoc documentation were followed by the description for the
wrong attribute. This patch reorders the descriptions to match the code
snippets.
Make sure people know the book is free oline
I've used the tutorial a number of times to relearn rust basics. When i saw this for a moment I was sad thinking it had been taken offline.
Fix null exclusions in grammar docs
The grammar documentation incorrectly says that comments, character literals,
and string literals may not include null.
Fix grammar documentation wrt Unicode identifiers
The grammar defines identifiers in terms of XID_start and XID_continue,
but this is referring to the unstable non_ascii_idents feature.
The documentation implies that non_ascii_idents is forthcoming, but this
is left over from pre-1.0 documentation; in reality, non_ascii_idents
has been without even an RFC for several years now, and will not be
stabilized anytime soon. Furthermore, according to the tracking issue at
https://github.com/rust-lang/rust/issues/28979 , it's highly
questionable whether or not this feature will use XID_start or
XID_continue even when or if non_ascii_idents is stabilized.
This commit fixes this by respecifying identifiers as the usual
[a-zA-Z_][a-zA-Z0-9_]*
The grammar defines identifiers in terms of XID_start and XID_continue,
but this is referring to the unstable non_ascii_idents feature.
The documentation implies that non_ascii_idents is forthcoming, but this
is left over from pre-1.0 documentation; in reality, non_ascii_idents
has been without even an RFC for several years now, and will not be
stabilized anytime soon. Furthermore, according to the tracking issue at
https://github.com/rust-lang/rust/issues/28979 , it's highly
questionable whether or not this feature will use XID_start or
XID_continue even when or if non_ascii_idents is stabilized.
This commit fixes this by respecifying identifiers as the usual
[a-zA-Z_][a-zA-Z0-9_]*
lint: deny incoherent_fundamental_impls by default
Warn the ecosystem of the pending intent-to-disallow in #49799.
There are 4 ICEs on my machine, look unrelated (having happened before in https://github.com/rust-lang/rust/issues/49146#issuecomment-384473523)
```rust
thread 'main' panicked at 'assertion failed: position <= slice.len()', libserialize/leb128.rs:97:1
```
```
[run-pass] run-pass/allocator/xcrate-use2.rs
[run-pass] run-pass/issue-12133-3.rs
[run-pass] run-pass/issue-32518.rs
[run-pass] run-pass/trait-default-method-xc-2.rs
```
r? @nikomatsakis
Bury Error::description()
Second attempt of #49536https://github.com/rust-lang/rfcs/pull/2230
The exact wording of the default implementation is still up in the air, but I think it's a detail that can be amended later.
Add "the Rustc book"
This PR introduces a new book into the documentation, "The rustc book". We already have books for Cargo, and for Rustdoc, rustc should have some too. This book is focused on *users* of rustc, and provides a nice place to write documentation for users.
I haven't put content here, but plan on scaffolding it out very soon, and wanted this PR open for a few discussions first. One of those is "what exactly should said TOC be?" I plan on having a proposed one up tomorrow, but figured I'd let people know to start thinking about it now.
The big one is that we also will want to put https://github.com/rust-lang-nursery/rustc-guide in-tree as well, and the naming is... tough. I'm proposing:
* doc.rust-lang.org/rustc is "The Rustc book", to mirror the other tools' books.
* doc.rust-lang.org/rustc-contribution is "The Rustc contribution guide", and contains that book
@nikomatsakis et al, any thoughts on this? I'm not attached to it in particular, but had to put something together to get this discussion going. I think mirroring the other tools is a good idea for this work, but am not sure where exactly that leaves yours.
Fixes https://github.com/rust-docs/team/issues/11
rustdoc: port the -C option from rustc
Blocked on https://github.com/rust-lang/rust/pull/49864. The included test won't work without those changes, so this PR includes those commits as well.
When documenting items that require certain target features, it helps to be able to force those target features into existence. Rather than include a flag just to parse those features, i instead decided to port the `-C` flag from rustc in its entirety. It takes the same parameters, because it runs through the same parsing function. This has the added benefit of being able to control the codegen of doctests as well.
One concern i have with the flag is that i set it to stable here. My rationale is that it is a direct port of functionality on rustc that is currently stable, used only in mechanisms that it is originally used for. If needed, i can set it back to be unstable.
