tree 25ec5a06e7a8510d733e2b468ad2df936d9c6617
parent d31e02004d860452bc7273f002f6890d0adc94fa
author Philipp Wollermann <philwo@chromium.org> 1782203345 +0900
committer gn-scoped@luci-project-accounts.iam.gserviceaccount.com <gn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1782345266 -0700

ninja_rust_binary_target_writer: link C++-reachable transitive rlibs

A rustc-driven link (rust_bin/cdylib/dylib) only links rlibs reachable
through the Rust crate graph (--extern + crate metadata). Rust libraries
reachable only through a C++ dependency were dropped from the link,
producing undefined cxx-bridge symbols for bridges whose Rust half lives
behind a C++ target (e.g. //base's rust_logger, serde_json_lenient).

The C++ linker path already handles this via the "rlibs" ninja variable
(NinjaCBinaryTargetWriter). Mirror it for final Rust targets: walk the
inherited library closure and link, as an archive via the existing
nonrustdeps -Clink-arg path, any RUST_LIBRARY that rustc does not link
itself. The "rustc links it" set is computed precisely as the
crate-graph closure of the --extern (directly-accessible) crates, so
rlibs reachable purely through rust deps are not passed twice.

Updates RlibInLibrary and TransitiveRustDepsThroughSourceSet goldens,
which previously asserted the (buggy) dropped-rlib behavior.

Bug: 513478482
Change-Id: I069dde441c0e1648f39562f18d59e0efde125038
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/23360
Commit-Queue: Philipp Wollermann <philwo@chromium.org>
Reviewed-by: Takuto Ikuta <tikuta@google.com>
Reviewed-by: Matt Stark <msta@google.com>