claude
0553a6b956
CI / shellcheck + selftests (pull_request) Skipped
Two review findings on #16. The `out/` discriminator keyed on Cargo's record of a build-script execution, which Cargo writes only AFTER the script exits successfully. A build script that populates OUT_DIR and then fails leaves a unit with no record at all, so its OUT_DIR read as a compile unit's artifact directory and stayed shared — a regression against the old `-name build` selection, which real-copied that state by construction. Reproduced on cargo 1.93.1 stable. An `out` directory now stays shared only when two independent signals agree: it holds an `.rlib`/`.rmeta` of its own, and its unit carries no execution record. Either one missing real-copies it. The cost is unchanged to the byte — the newly-unshared directories hold only executables and `*.d`, both already privately owned by the file rules. The live linked-test-binary scenario was built on the lib+bin probe crate, whose test binaries relink to a fresh inode — a shape gitdan-actions#17 records as measured safe. Both halves passed green against the unfixed selection on dep-info mutations the previous scenario already covers. It now builds a bin-only crate with a unit test, reads only executables, and skips loudly with a warning rather than passing quietly if the toolchain does not exhibit the rewrite at all. Also: drop a clause asserting the linker writes in place "whenever the path has no other hard link", which this change's own evidence denies; move the load-bearing comment block back above `unshare_mutable_paths`; correct a superseded 99.998% figure; and record both cost rows in the README rather than only the flattering whole-tree one.