uniffi-rs errors reading from large release staticlib ELF binaries

[Johennes]

With UBRN from 7afb49b and the following ubrn.yaml

---
crate:
  repo: https://github.com/matrix-org/matrix-rust-sdk
  rev: 19b9a73ecc3e31d502dbf0c5850bfdfaddf02afe # matrix-sdk-ffi/20241008
  manifestPath: bindings/matrix-sdk-ffi/Cargo.toml
android:
  cargoExtras: []
  directory: android
  jniLibs: src/main/jniLibs
  targets:
    - arm64-v8a
    - armeabi-v7a
ios:
  cargoExtras: []
  directory: ios
  targets:
    - aarch64-apple-ios
    - aarch64-apple-ios-sim
  xcodebuildExtras: []
  frameworkName: build/RnMatrixRustSdk
noOverwrite: []
turboModule:
  cpp: cpp
  ts: src
bindings:
  cpp: cpp/generated
  ts: src/generated

yarn ubrn build android --release --config ubrn.yaml --and-generate fails for me:

...
-- Copying into jniLibs directory
rm -Rf /Users/jm/Code/react-native-matrix-sdk/android/src/main/jniLibs
cp /Users/jm/Code/react-native-matrix-sdk/rust_modules/matrix-rust-sdk/target/aarch64-linux-android/release/libmatrix_sdk_ffi.a /Users/jm/Code/react-native-matrix-sdk/android/src/main/jniLibs/arm64-v8a/libmatrix_sdk_ffi.a
cp /Users/jm/Code/react-native-matrix-sdk/rust_modules/matrix-rust-sdk/target/armv7-linux-androideabi/release/libmatrix_sdk_ffi.a /Users/jm/Code/react-native-matrix-sdk/android/src/main/jniLibs/armeabi-v7a/libmatrix_sdk_ffi.a
Error: Failed to extract data from archive member `matrix_sdk_ffi.matrix_sdk_ffi.d37ea2d03792f472-cgu.12.rcgu.o`

@zzorba have you tried UBRN on the Rust SDK in release mode yet by any chance?

[zzorba]

We primarily build release, to avoid the extra disk space. But I haven't run the latest version and we have a slightly modified build script still.

I will test tomorrow to confirm against main.

[Johennes]

Doing the same for iOS works, interestingly, as yarn ubrn build ios --release --config ubrn.yaml --and-generate doesn't fail for me.

As a workaround one can just build for both platforms and then run yarn generate all, pointing it to the iOS library:

yarn ubrn generate all --config ubrn.yaml build/RnMatrixRustSdk.xcframework/ios-arm64/libmatrix_sdk_ffi.a

[jhugman]

From your description, I thought it may be something to do with stripping of the Android binaries. This is done here.

However, I just quickly tried to reproduce, and could not. :( (on main)

I have not yet tried with 7afb49b .

[Johennes]

Hm, interesting. I'm not sure if it matters but I'm on rustc 1.81.0 (eeb90cda1 2024-09-04).

[Johennes]

So I've tried main and manually disabled stripping but am still left with the same error.

$ ../uniffi-bindgen-react-native/bin/cli build android --release --config ubrn.yaml --and-generate
Running cd "/Users/jm/Code/react-native-matrix-sdk/rust_modules/matrix-rust-sdk/bindings/matrix-sdk-ffi" && "cargo" "ndk" "--manifest-path" "/Users/jm/Code/react-native-matrix-sdk/rust_modules/matrix-rust-sdk/bindings/matrix-sdk-ffi/Cargo.toml" "--target" "arm64-v8a" "--platform" "21" "--no-strip" "--" "build" "--release"
    Building arm64-v8a (aarch64-linux-android)
    ...
    Finished `release` profile [optimized] target(s) in 10m 11s
-- Copying into jniLibs directory
rm -Rf /Users/jm/Code/react-native-matrix-sdk/android/src/main/jniLibs
cp /Users/jm/Code/react-native-matrix-sdk/rust_modules/matrix-rust-sdk/target/aarch64-linux-android/release/libmatrix_sdk_ffi.a /Users/jm/Code/react-native-matrix-sdk/android/src/main/jniLibs/arm64-v8a/libmatrix_sdk_ffi.a
Error: Failed to extract data from archive member `matrix_sdk_ffi.matrix_sdk_ffi.d37ea2d03792f472-cgu.12.rcgu.o`

Caused by:
    Unexpected metadata code: 255

Judging by the error message, it stems from https://github.com/mozilla/uniffi-rs/blob/438778213f6014dc44204acd3e6b92c29b439405/uniffi_bindgen/src/macro_metadata/extract.rs#L149. So might not actually be a UBRN issue.

[Johennes]

Caused by:
    Unexpected metadata code: 255

I don't recall seeing this yesterday but I might have just missed it. It appears to originate from https://github.com/mozilla/uniffi-rs/blob/438778213f6014dc44204acd3e6b92c29b439405/uniffi_meta/src/reader.rs#L62.

[jhugman]

@Johennes Are you still seeing this?

[Johennes]

I tried rebuilding and regenerating matrix-rust-sdk@matrix-sdk-ffi/20241008 with UBRN from current main and, sadly, its the same error.

[jhugman]

Stack trace from reproduction:

Error: Failed to extract data from archive member `matrix_sdk_ffi.matrix_sdk_ffi.bf8c76dbb4572677-cgu.07.rcgu.o`

Caused by:
    Unexpected metadata code: 88

Stack backtrace:
   0: std::backtrace_rs::backtrace::libunwind::trace
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/../../backtrace/src/backtrace/libunwind.rs:116:5
   1: std::backtrace_rs::backtrace::trace_unsynchronized
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2: std::backtrace::Backtrace::create
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/backtrace.rs:331:13
   3: anyhow::error::<impl anyhow::Error>::msg
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.86/src/backtrace.rs:27:14
   4: anyhow::__private::format_err
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.86/src/lib.rs:692:13
   5: uniffi_meta::reader::MetadataReader::read_metadata
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_meta-0.28.0/src/reader.rs:62:18
   6: uniffi_meta::reader::read_metadata
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_meta-0.28.0/src/reader.rs:10:5
   7: uniffi_meta::Metadata::read
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_meta-0.28.0/src/lib.rs:485:9
   8: uniffi_bindgen::macro_metadata::extract::ExtractedItems::extract_item
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_bindgen-0.28.0/src/macro_metadata/extract.rs:178:25
   9: uniffi_bindgen::macro_metadata::extract::extract_from_elf
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_bindgen-0.28.0/src/macro_metadata/extract.rs:53:13
  10: uniffi_bindgen::macro_metadata::extract::extract_from_bytes
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_bindgen-0.28.0/src/macro_metadata/extract.rs:29:29
  11: uniffi_bindgen::macro_metadata::extract::extract_from_archive
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_bindgen-0.28.0/src/macro_metadata/extract.rs:138:18
  12: uniffi_bindgen::macro_metadata::extract::extract_from_bytes
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_bindgen-0.28.0/src/macro_metadata/extract.rs:32:37
  13: uniffi_bindgen::macro_metadata::extract::extract_from_library
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_bindgen-0.28.0/src/macro_metadata/extract.rs:24:5
  14: uniffi_bindgen::library_mode::find_components
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_bindgen-0.28.0/src/library_mode.rs:108:17
  15: uniffi_bindgen::library_mode::generate_bindings
             at /Users/jhugman/.cargo/registry/src/index.crates.io-6f17d22bba15001f/uniffi_bindgen-0.28.0/src/library_mode.rs:49:26
  16: ubrn_bindgen::bindings::BindingsArgs::run
             at /Users/jhugman/workspaces/react-native-uniffi/work/uniffi-bindgen-react-native/crates/ubrn_bindgen/src/bindings/mod.rs:127:13
  17: uniffi_bindgen_react_native::generate::GenerateAllCommand::run
             at /Users/jhugman/workspaces/react-native-uniffi/work/uniffi-bindgen-react-native/crates/ubrn_cli/src/generate.rs:122:13
  18: uniffi_bindgen_react_native::generate::GenerateCmd::run
             at /Users/jhugman/workspaces/react-native-uniffi/work/uniffi-bindgen-react-native/crates/ubrn_cli/src/generate.rs:52:17
  19: uniffi_bindgen_react_native::generate::GenerateArgs::run
             at /Users/jhugman/workspaces/react-native-uniffi/work/uniffi-bindgen-react-native/crates/ubrn_cli/src/generate.rs:22:9
  20: uniffi_bindgen_react_native::cli::CliCmd::run
             at /Users/jhugman/workspaces/react-native-uniffi/work/uniffi-bindgen-react-native/crates/ubrn_cli/src/cli.rs:40:34
  21: uniffi_bindgen_react_native::main
             at /Users/jhugman/workspaces/react-native-uniffi/work/uniffi-bindgen-react-native/crates/ubrn_cli/src/main.rs:24:5
  22: core::ops::function::FnOnce::call_once
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/core/src/ops/function.rs:250:5
  23: std::sys::backtrace::__rust_begin_short_backtrace
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/sys/backtrace.rs:152:18
  24: std::rt::lang_start::{{closure}}
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/rt.rs:162:18
  25: core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/core/src/ops/function.rs:284:13
  26: std::panicking::try::do_call
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/panicking.rs:557:40
  27: std::panicking::try
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/panicking.rs:521:19
  28: std::panic::catch_unwind
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/panic.rs:350:14
  29: std::rt::lang_start_internal::{{closure}}
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/rt.rs:141:48
  30: std::panicking::try::do_call
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/panicking.rs:557:40
  31: std::panicking::try
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/panicking.rs:521:19
  32: std::panic::catch_unwind
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/panic.rs:350:14
  33: std::rt::lang_start_internal
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/rt.rs:141:20
  34: std::rt::lang_start
             at /rustc/eeb90cda1969383f56a2637cbd3037bdf598841c/library/std/src/rt.rs:161:17
  35: _main

[jhugman]

Trying to characterize this issue with the given YAML.

Once checked out, I'm building the matrix library, from within the rust_modules/matrix-rust-sdk directory.

Then feeding the resulting lib into the bundled uniffi-bindgen within that library. i.e. no uniffi-bindgen-react-native code.

This works:

$ cargo run --manifest-path uniffi-bindgen/Cargo.toml  -- generate --language kotlin --library target/aarch64-linux-android/release/libmatrix_sdk_ffi.so  --out-dir kt

We can also get swift to generate from this same library:

$ cargo run --manifest-path uniffi-bindgen/Cargo.toml  -- generate --language switt --library target/aarch64-linux-android/release/libmatrix_sdk_ffi.so  --out-dir swift

Swift is normally generated from a .a file, and python and kotlin usually need a .so file.

We seem to be having problems with the reading of staticlib release builds; we'd expect this to work, even though it's a build for a different architecture. However:

$ cargo run --manifest-path uniffi-bindgen/Cargo.toml  -- generate --language swift --library target/aarch64-linux-android/release/libmatrix_sdk_ffi.a  --out-dir swift
    Finished `dev` profile [unoptimized] target(s) in 0.11s
     Running `target/debug/uniffi-bindgen generate --language swift --library target/aarch64-linux-android/release/libmatrix_sdk_ffi.a --out-dir swift`
Failed to extract data from archive member `matrix_sdk_ffi.matrix_sdk_ffi.bf8c76dbb4572677-cgu.07.rcgu.o`

The debug build seems to work:

$ cargo run --manifest-path uniffi-bindgen/Cargo.toml  -- generate --language swift --library target/aarch64-linux-android/debug/libmatrix_sdk_
ffi.a  --out-dir swift
    Finished `dev` profile [unoptimized] target(s) in 0.11s
     Running `target/debug/uniffi-bindgen generate --language swift --library target/aarch64-linux-android/debug/libmatrix_sdk_ffi.a --out-dir swift`

So, what is different about the release build coming out of cargo ndk, that uniffi-rs cannot read?

I'd also like to reduce the size of the library that is being built: @Johennes has reported

Caused by:
    Unexpected metadata code: 255

and I am now seeing:

Caused by:
    Unexpected metadata code: 88

[jhugman]

I think we're firmly in the territory of "not holding it wrong, but not holding it as expected".

Cutting out uniffi-bindgen-react-native altogether, I'm building the matrix sdk ffi binding with:

cd /private/tmp/turbomodule-tests/122-repro/rust_modules/matrix-rust-sdk/bindings/matrix-sdk-ffi && \
  cargo ndk \
  --manifest-path /private/tmp/turbomodule-tests/122-repro/rust_modules/matrix-rust-sdk/bindings/matrix-sdk-ffi/Cargo.toml \
  --target arm64-v8a \
  --platform 21 --no-strip -- \
  build --release

I have lightly instrumented uniffi-rs to output the extracted metadata and types. Here is the output from the aarch64-linux-android/debug build.

And here is the output from aarch64-linux-android/release:

Metadata symbol UNIFFI_META_MATRIX_SDK_FFI_INTERFACE_ENCRYPTION
thread 'main' panicked at uniffi_meta/src/metadata.rs:84:18:
XXXX UNKNOWN ITEM 88 XXXX
stack backtrace:
   0: rust_begin_unwind
             at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:647:5
   1: core::panicking::panic_fmt
             at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/panicking.rs:72:14
   2: uniffi_meta::metadata::codes::metadata_as_str
             at ./uniffi_meta/src/metadata.rs:84:18
   3: uniffi_meta::reader::MetadataReader::read_metadata
             at ./uniffi_meta/src/reader.rs:39:33
   4: uniffi_meta::reader::read_metadata
             at ./uniffi_meta/src/reader.rs:10:5
   5: uniffi_meta::Metadata::read
             at ./uniffi_meta/src/lib.rs:505:9
   6: uniffi_bindgen::macro_metadata::extract::ExtractedItems::extract_item
             at ./uniffi_bindgen/src/macro_metadata/extract.rs:184:25
   7: uniffi_bindgen::macro_metadata::extract::extract_from_elf
             at ./uniffi_bindgen/src/macro_metadata/extract.rs:53:13
   8: uniffi_bindgen::macro_metadata::extract::extract_from_bytes
             at ./uniffi_bindgen/src/macro_metadata/extract.rs:29:29
   9: uniffi_bindgen::macro_metadata::extract::extract_from_archive
             at ./uniffi_bindgen/src/macro_metadata/extract.rs:143:18
  10: uniffi_bindgen::macro_metadata::extract::extract_from_bytes
             at ./uniffi_bindgen/src/macro_metadata/extract.rs:32:37
  11: uniffi_bindgen::macro_metadata::extract::extract_from_library
             at ./uniffi_bindgen/src/macro_metadata/extract.rs:24:5
  12: uniffi_bindgen::library_mode::find_components
             at ./uniffi_bindgen/src/library_mode.rs:104:17
  13: uniffi_bindgen::library_mode::generate_bindings
             at ./uniffi_bindgen/src/library_mode.rs:46:26
  14: uniffi::cli::uniffi_bindgen::gen_library_mode
             at ./uniffi/src/cli/uniffi_bindgen.rs:207:38
  15: uniffi::cli::uniffi_bindgen::run_main
             at ./uniffi/src/cli/uniffi_bindgen.rs:297:17
  16: uniffi::cli::uniffi_bindgen_main
             at ./uniffi/src/cli/mod.rs:9:21
  17: uniffi_bindgen::main
             at ./cli/src/main.rs:2:5
  18: core::ops::function::FnOnce::call_once
             at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

i.e. it seems to be failing at the first metadata symbol UNIFFI_META_MATRIX_SDK_FFI_INTERFACE_ENCRYPTION with an unknown metadata item with code 88.

I don't really understand how the metadata is being written or how it differs between debug and release.

[jhugman]

This will be fixed by mozilla/uniffi-rs#2286.