`cargo install rustpatcher` on MacOS fails with LLVM error

[b5]

I get the following when I try to compile rustpatcher on macos:

   Compiling clap v4.5.48
   Compiling nix v0.30.1
   Compiling iroh-relay v0.92.0
   Compiling distributed-topic-tracker v0.2.1
   Compiling rustpatcher v0.2.0 (/Users/b5/code/rustpatcher/crates/rustpatcher)
rustc-LLVM ERROR: Global variable 'EMBED_REGION' has an invalid section specifier '.embedded_signature': mach-o section specifier requires a segment and section separated by a comma.
error: could not compile `rustpatcher` (lib)

Caused by:
  process didn't exit successfully: `rustc --crate-name rustpatcher --edition=2024 crates/rustpatcher/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --diagnostic-width=65 --crate-type lib --emit=dep-info,metadata,link -C opt-level=3 -C embed-bitcode=no --check-cfg 'cfg(docsrs,test)' --check-cfg 'cfg(feature, values())' -C metadata=2901c0a9e98e0eaf -C extra-filename=-045451d6b36b1e01 --out-dir /Users/b5/.cargo/build/release/deps -C strip=debuginfo -L dependency=/Users/b5/.cargo/build/release/deps --extern actor_helper=/Users/b5/.cargo/build/release/deps/libactor_helper-926eea97aa42afd1.rmeta --extern anyhow=/Users/b5/.cargo/build/release/deps/libanyhow-7f297b5bfe55623b.rmeta --extern chrono=/Users/b5/.cargo/build/release/deps/libchrono-cd8751e78c4292f0.rmeta --extern clap=/Users/b5/.cargo/build/release/deps/libclap-848d54e91801397d.rmeta --extern ctor=/Users/b5/.cargo/build/release/deps/libctor-dbf00029c0a5da41.rmeta --extern distributed_topic_tracker=/Users/b5/.cargo/build/release/deps/libdistributed_topic_tracker-338d678e385d2d16.rlib --extern ed25519_dalek=/Users/b5/.cargo/build/release/deps/libed25519_dalek-fc79b6c2d50227cb.rmeta --extern iroh=/Users/b5/.cargo/build/release/deps/libiroh-215361f75994d38c.rlib --extern nix=/Users/b5/.cargo/build/release/deps/libnix-56e65c93fe9f9d8c.rmeta --extern once_cell=/Users/b5/.cargo/build/release/deps/libonce_cell-88905b673f589f4e.rmeta --extern postcard=/Users/b5/.cargo/build/release/deps/libpostcard-3d96d308a77ec156.rmeta --extern rand=/Users/b5/.cargo/build/release/deps/librand-b1b97ae05411d135.rmeta --extern rustpatcher_macros=/Users/b5/.cargo/build/release/deps/librustpatcher_macros-07b9fca49396c253.dylib --extern self_replace=/Users/b5/.cargo/build/release/deps/libself_replace-c84ec20728e87c88.rmeta --extern serde=/Users/b5/.cargo/build/release/deps/libserde-ef603eff6537e737.rmeta --extern serde_json=/Users/b5/.cargo/build/release/deps/libserde_json-9dc8be5a3a6c596e.rmeta --extern sha2=/Users/b5/.cargo/build/release/deps/libsha2-7488e84e9597bdd8.rmeta --extern tempfile=/Users/b5/.cargo/build/release/deps/libtempfile-890fdce86d34698e.rmeta --extern tokio=/Users/b5/.cargo/build/release/deps/libtokio-467fd5758b24b5fb.rmeta --extern tracing=/Users/b5/.cargo/build/release/deps/libtracing-24efa89ba35b0f74.rmeta --extern tracing_subscriber=/Users/b5/.cargo/build/release/deps/libtracing_subscriber-61c3fee619f66ffa.rmeta --extern z32=/Users/b5/.cargo/build/release/deps/libz32-0736869420650840.rmeta -L native=/Users/b5/.cargo/build/release/build/ring-68b1f4d06aac331b/out -L native=/Users/b5/.cargo/build/release/build/blake3-5c8b6236e7bf6b10/out` (exit status: 101)

Seems like it's running into platform-specific requirements of the .embedded_signature entry in the link section

[rustonbsd]

Hi @b5,

thank you for the logs! I am looking into it right now.

[b5]

Happy to play "run this on a mac" whack-a-mole!

[rustonbsd]

Just opened a PR with now custom sections for macos.
The issue was that macos expects sections to be prefixed:

#[cfg_attr(target_os = "macos", unsafe(link_section = "__DATA,__embsig"))]

and apparently linker sections should be shorter then 16 or 12 chars so I shortened the section name on all platforms.

After the rust build process macos uses codesign to sign the binary. When we now overwrite with rustpatcher sign ..., we run into a invalid signature error either on the codesign or the rustpatcher sign. Solution is basically:

1. build --release
2. rustpatcher sign (cut off macos code sign section for our signature, always at end, using goblin)
3. re-sign with codesign (this is done automatically in the rustpatcher xtask)
4. when verify, strip the codesign like rustpatcher sign does for equal rustpatcher signature before and after codesign.
   =>
5. No more signing conflicts

I will test on linux and win tomorrow.

@b5 if you want to test it on your mac you can find run instructions in the PR #5 or here:

NOTE: for some reason you have to run cargo run --release --bin rustpatcher sign ../../target/release/examples/simple --key-file ../../owner_key_example twice for it to work on macos. i am guessing the xtask's final mac specific codesign call seems to fail quietly.

cd rustpatcher/
git checkout macos-embed-region-error
cargo build --release --example simple
cargo run --release --bin rustpatcher sign target/release/examples/simple --key-file owner_key_example
target/release/examples/simple

I will pick it back up tomorrow.

[rustonbsd]

Hi @b5,

everything is running on macos on my end now. I also added an e2e, github actions test for easier detection of platform failures, turns out windows is also not running (nix libc not available on win). But macos and linux seem to run well now.

Tangent: I also fixed a bug that would prevent the execv Result from being evaluated since it was in a tracing::info! statement and as it turns out if tracing logs aren't enabled, the execv never runs and the process exits (fixed now). So updating to this version is almost a must!

If you happened to test again on macos, please let me know if the signing issue has been resolved.
I am pushing v0.2.1 to crates.io, should be available as a new release in 15min from now.

Merged PR: #5

[rustonbsd]

I will close this for now. If you still have problems let me know and i will reopen :)