3e70dfd655
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.
Rust documentations
Building
To generate all the docs, follow the "Building Documentation" instructions in the README in the root of the repository. This will convert the distributed Markdown docs to HTML and generate HTML doc for the books, 'std' and 'extra' libraries.
To generate HTML documentation from one source file/crate, do something like:
rustdoc --output html-doc/ --output-format html ../src/libstd/path.rs
(This, of course, requires a working build of the rustdoc tool.)
Additional notes
To generate an HTML version of a doc from Markdown manually, you can do something like:
rustdoc reference.md
(reference.md being the Rust Reference Manual.)
An overview of how to use the rustdoc command is available in the docs.
Further details are available from the command line by with rustdoc --help.