`exported_private_dependencies` lint only take effect in innermost dependency

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Problem

The exported_private_dependencies lint only take affect in the innermost dependency in a recursively dependent environment.

This inspired by https://github.com/rust-lang/rust/issues/44663#issuecomment-1851227083.

Steps

In order to prove this problem, I purposely contructed a code repository, here

in the repository, the crates folder has three crates,

• grandparent_dep, the init crate provied the pub struct
• parent_dep, the middle crate, add grandparent_dep as public and reexport pub struct from grandparent_dep
• pub_dep, the outmost crate, add parent_dep as public and reexport pub struct from parent_dep

(the crates in crates can be treated as download from respority(like github, crates.io))

in src/lib.rs, add pub_dep as dependency but private.

After downloading the resposity,

1、 run cargo build, no lint warning message
2、 change the public = false in crates/pub_dep/Cargo.toml, then run cargo build, no lint warning message
3、 change the public = false in crates/parent_dep/Cargo.toml, run cargo build and a lint warning message comes up.

cargo build
   Compiling parent_dep v0.1.0 (/root/workspace/recursive_pub_reexport/crates/parent_dep)
   Compiling pub_dep v0.1.0 (/root/workspace/recursive_pub_reexport/crates/pub_dep)
   Compiling simple v0.1.0 (/root/workspace/recursive_pub_reexport)
warning: type `FromPriv` from private dependency 'grandparent_dep' in public interface
 --> src/lib.rs:3:1
  |
3 | pub fn use_pub(_: pub_dep::FromPriv) {}
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(exported_private_dependencies)]` on by default

Possible Solution(s)

The focus of this issue is to verify whether there is a problem with the current situation, so the solution will not be considered for the time being.

Notes

No response

Version

cargo 1.76.0-nightly (623b78849 2023-12-02)
release: 1.76.0-nightly
commit-hash: 623b788496b3e51dc2f9282373cf0f6971a229b5
commit-date: 2023-12-02
host: x86_64-unknown-linux-gnu
libgit2: 1.7.1 (sys:0.18.1 vendored)
libcurl: 8.4.0-DEV (sys:0.4.68+curl-8.4.0 vendored ssl:OpenSSL/1.1.1u)
ssl: OpenSSL 1.1.1u  30 May 2023
os: Ubuntu 22.04 (jammy) [64-bit]

Start with the linked recursive_pub_reexport repository, reviewing crates/grandparent_dep, crates/parent_dep, crates/pub_dep, and the root src/lib.rs. Run cargo build while changing public in each dependency's Cargo.toml and compare the lint output. Done means confirming and characterizing the recursive exported_private_dependencies behavior; the issue does not specify an implementation or test location.