Rollup of 8 pull requests

[Dylan-DPC-zz]

Successful merges:

• clarify rules for ZST Boxes #77844 (clarify rules for ZST Boxes)
• Refactor the abi handling code a bit #79067 (Refactor the abi handling code a bit)
• Fix links to extern types in rustdoc (fixes #78777) #79182 (Fix links to extern types in rustdoc (fixes rustdoc: Referencing methods on extern_types does not resolve #78777))
• Exhaustively match in variant count instrinsic #79231 (Exhaustively match in variant count instrinsic)
• Direct RUSTC_LOG (tracing/log) output to stderr instead of stdout. #79238 (Direct RUSTC_LOG (tracing/log) output to stderr instead of stdout.)
• Fix typos #79256 (Fix typos)
• Get rid of some doctree items #79264 (Get rid of some doctree items)
• Support building clone shims for arrays with generic size #79272 (Support building clone shims for arrays with generic size)

Failed merges:

r? @ghost
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