Consider removing sections about std/core libraries

[rylev]

The library team has a guide for the standard library. We should consider removing some chapters like https://rustc-dev-guide.rust-lang.org/stability.html from the rustc-dev-guide. First we should ensure that the content being removed is already reflected in the library guide.

[joshtriplett]

I think we should also merge std-dev-guide into the rust doc directory alongside rustc-dev-guide.

[jyn514]

Long term I don't think either should be in-tree: https://github.com/rust-lang/rust/pull/81848#issuecomment-787588985. But I guess it makes sense for the std guide to be the same as the rustc guide for now.

[Mark-Simulacrum]

It looks like those comments were written in reaction to the rather large size of the submodule, which looks to be dominated by a few html files for self profile output. Maybe we should put those files on S3 or otherwise not track them in git? And then the rest could be managed via subtree or similar.

[jyn514]

Well, there's also some overhead to having the repo in both places, either @ehuss has to update the submodule when he updates books or someone needs to be in charge of syncing back and forth. It seems a little silly when there's not much benefit from having it in-tree.

[joshtriplett]

On Thu, Jul 01, 2021 at 11:03:55AM -0700, Joshua Nelson wrote:

Well, there's also some overhead to having the repo in both places, either @ehuss has to update the submodule when he updates books or someone needs to be in charge of syncing back and forth. It seems a little silly when there's not much benefit from having it in-tree.

I personally would love to see it just merged as a subtree and maintained in-tree; it documents rustc, so having it in rustc seems sensible.