Move Generics from MethodSig to TraitItem and ImplItem
As part of `rust-impl-period/WG-compiler-traits`, we want to "lift" `Generics` from `MethodSig` into `TraitItem` and `ImplItem`. This is in preparation for adding associated type generics. (https://github.com/rust-lang/rust/issues/44265#issuecomment-331172238)
Currently this change is only made in the AST. In the future, it may also impact the HIR. (Still discussing)
To understand this PR, it's probably best to start from the changes to `ast.rs` and then work your way to the other files to understand the far reaching effects of this change.
r? @nikomatsakis
rustdoc: add a primitive page for "unit"
In `src/libstd/primitive_docs.rs`, a `#[doc(primitive = "unit")]`
section has sat long neglected. This patch teaches rustdoc to recognize
"unit", and steals its trait implementations away from the tuple page.
Deprecate several flags in rustdoc
Part of #44136
cc @rust-lang/dev-tools @rust-lang/docs
This is a very basic PR to start deprecating some flags; `rustdoc` doesn't really have fancy output options like `rustc` does, so I went with `eprintln!`. Happy to change it if people feel that's not appropriate.
Also, I have no idea if we can or should write tests here, so I didn't try. If someone feels strongly about it, then let's do it, but given that the only outcome here is a side effect...
In `src/libstd/primitive_docs.rs`, a `#[doc(primitive = "unit")]`
section has sat long neglected. This patch teaches rustdoc to recognize
"unit", and steals its trait implementations away from the tuple page.
rustbuild: Support specifying archiver and linker explicitly
With this patch `x.py test` passes without toolchain being in `PATH` if `cc`, `cxx`, `ar`, `linker` and `gdb` are specified in `config.toml` (except for a few `run-make` tests using `nm`).
Fixes https://github.com/rust-lang/rust/issues/41821
r? @Mark-Simulacrum
some low-hanging rustdoc optimizations
There were a few discussions earlier today in #rust-internals about the syscall usage and overall performance of rustdoc. This PR is intended to pick some low-hanging fruit and try to rein in some of the performance issues of rustdoc.
Add x86_64-unknown-linux-gnux32 target
This adds X32 ABI support for Linux on X86_64. Let's package and dist it so we can star testing libc, libstd, etc.
Fixes https://github.com/rust-lang/rfcs/issues/1339
doc-test: In Markdown tests, Use all of `<h1>` to `<h6>` as the test name
This mainly simplifies debugging error index tests, as the error codes are `<h2>`s in the huge document containing all codes.
let rustdoc print the crate version into docs
This PR adds a new unstable flag to rustdoc, `--crate-version`, which when present will add a new entry to the sidebar of the root module, printing the given version number:

Closes#24336
(The WIP status is because i don't want to merge this until i can get the std docs to use it, which i need help from rustbuild people to make sure i get right.)
Remove support for the PNaCl target (le32-unknown-nacl)
This removes support for the `le32-unknown-nacl` target which is currently supported by rustc on tier 3. Despite the "nacl" in the name, the target doesn't output native code (x86, ARM, MIPS), instead it outputs binaries in the PNaCl format.
There are two reasons for the removal:
* Google [has announced](https://blog.chromium.org/2017/05/goodbye-pnacl-hello-webassembly.html) deprecation of the PNaCl format. The suggestion is to migrate to wasm. Happens we already have a wasm backend!
* Our PNaCl LLVM backend is provided by the fastcomp patch set that the LLVM fork used by rustc contains in addition to vanilla LLVM (`src/llvm/lib/Target/JSBackend/NaCl`). Upstream LLVM doesn't have PNaCl support. Removing PNaCl support will enable us to move away from fastcomp (#44006) and have a lighter set of patches on top of upstream LLVM inside our LLVM fork. This will help distribution packagers of Rust.
Fixes#42420