rust 1.82 + cross compiling to aarch64-apple-darwin results in iconv linker error

[rfairfax]

We have a project that uses zstd-sys, which in turn pulls in libiconv and libcharset dependencies. On rust 1.81 and prior cargo-zigbuild was able to link properly via what looks like the tbd files that cargo-zigbuild drops.

When we compile the same code with 1.82 we get an error like the following:

  = note: error: unable to find dynamic system library 'iconv' using strategy 'paths_first'. searched paths:
            /workspace/oss-repo/core/src/rust/target/aarch64-apple-darwin/debug/build/zstd-sys-5f411c27504b93ea/out/libiconv.tbd
            /workspace/oss-repo/core/src/rust/target/aarch64-apple-darwin/debug/build/zstd-sys-5f411c27504b93ea/out/libiconv.dylib
            /workspace/oss-repo/core/src/rust/target/aarch64-apple-darwin/debug/build/zstd-sys-5f411c27504b93ea/out/libiconv.so
            /workspace/oss-repo/core/src/rust/target/aarch64-apple-darwin/debug/build/zstd-sys-5f411c27504b93ea/out/libiconv.a
          error: unable to find dynamic system library 'charset' using strategy 'paths_first'. searched paths:
            /workspace/oss-repo/core/src/rust/target/aarch64-apple-darwin/debug/build/zstd-sys-5f411c27504b93ea/out/libcharset.tbd
            /workspace/oss-repo/core/src/rust/target/aarch64-apple-darwin/debug/build/zstd-sys-5f411c27504b93ea/out/libcharset.dylib
            /workspace/oss-repo/core/src/rust/target/aarch64-apple-darwin/debug/build/zstd-sys-5f411c27504b93ea/out/libcharset.so
            /workspace/oss-repo/core/src/rust/target/aarch64-apple-darwin/debug/build/zstd-sys-5f411c27504b93ea/out/libcharset.a

I'm not sure what combination of settings is tripping this up as the project is complex, but here's our repro:

# With Rust 1.82 installed

git clone --branch=develop https://github.com/filodb/FiloDB.git repro
cd repro/core/src/rust
cargo zigbuild --target aarch64-apple-darwin

[luketaverne]

Hi all, I’ve run into the same issue. It can be reproduced with a simple helloworld with the following steps on Ubuntu (20.04):

pyenv shell 3.10.0 # python version I used
python -m venv .venv
source .venv/bin/activate
pip install "maturin[zig]"

maturin new helloworld # press enter on pyo3
cd helloworld

# 1.81 works
rustup toolchain install 1.81
rustup target add aarch64-apple-darwin
rustup target add x86_64-apple-darwin
maturin build --release --target aarch64-apple-darwin -i python3.10 --zig # --zig invokes cargo-zigbuild
maturin build --release --target x86_64-apple-darwin -i python3.10 --zig 

# both compile, now do 1.82
rustup toolchain install 1.82
rustup target add aarch64-apple-darwin
rustup target add x86_64-apple-darwin
maturin build --release --target aarch64-apple-darwin -i python3.10 --zig
maturin build --release --target x86_64-apple-darwin -i python3.10 --zig

Gives the following error:

(.venv) luke@luke-desktop:~/maturin-zig/helloworld$ maturin build --release --target x86_64-apple-darwin -i python3.10 --zig
 Found pyo3 bindings
 Found CPython 3.10
 Using build options features from pyproject.toml
 Using `MACOSX_DEPLOYMENT_TARGET=10.12` for x86_64-apple-darwin by default
   Compiling unindent v0.2.3
   Compiling once_cell v1.20.2
   Compiling cfg-if v1.0.0
   Compiling pyo3-build-config v0.22.5
   Compiling libc v0.2.161
   Compiling memoffset v0.9.1
   Compiling pyo3-macros-backend v0.22.5
   Compiling pyo3-ffi v0.22.5
   Compiling pyo3 v0.22.5
   Compiling pyo3-macros v0.22.5
   Compiling helloworld v0.1.0 (/home/luke/maturin-zig/helloworld)
error: linking with `/home/luke/.cache/cargo-zigbuild/0.19.3/zigcc-x86_64-apple-darwin-db1e.sh` failed: exit status: 1
  |
  = note: env -u IPHONEOS_DEPLOYMENT_TARGET -u TVOS_DEPLOYMENT_TARGET -u XROS_DEPLOYMENT_TARGET LC_ALL="C" PATH="/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/bin:/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/bin:/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/bin:/home/luke/maturin-zig/.venv/bin:/usr/local/cuda/bin:/home/luke/.cargo/bin:/home/luke/.pyenv/shims:/home/luke/.pyenv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/snap/bin:/home/luke/.local/share/JetBrains/Toolbox/scripts" VSLANG="1033" ZERO_AR_DATE="1" "/home/luke/.cache/cargo-zigbuild/0.19.3/zigcc-x86_64-apple-darwin-db1e.sh" "-Wl,-exported_symbols_list" "-Wl,/tmp/rustctP7gYA/list" "-arch" "x86_64" "-m64" "/tmp/rustctP7gYA/symbols.o" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/helloworld.helloworld.39b5626b2ea3a229-cgu.0.rcgu.o" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/helloworld.helloworld.39b5626b2ea3a229-cgu.1.rcgu.o" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/helloworld.6mzpv3gfb9o9ritdksmol1jg7.rcgu.o" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/libpyo3-8f8a9608071a5f95.rlib" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/libcfg_if-91f3e21e04e8c380.rlib" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/libmemoffset-5ff88791c6a469df.rlib" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/libonce_cell-1d611e34cc186fc9.rlib" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/libpyo3_ffi-99f47721ff8d8e39.rlib" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/liblibc-da3b39af13a72771.rlib" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/libunindent-c611096cc0e65ddc.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libstd-61602592c271c404.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libpanic_unwind-aeb4058a408754f7.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libobject-2347acd1a76495bc.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libmemchr-2cacaa99e1370983.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libaddr2line-d22d75eab3ee9f91.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libgimli-d45a4af6567e40f5.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/librustc_demangle-629221368a04a8cc.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libstd_detect-ccf80679c2766d42.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libhashbrown-343b4303636920e6.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/librustc_std_workspace_alloc-4ade444259fc53a0.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libminiz_oxide-45c3b99287a6b825.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libadler-bc7af87c325a8997.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libunwind-94df3cb34810525c.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libcfg_if-c37598a755f715a4.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/liblibc-afe23bae68f053d8.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/liballoc-f4619dbb652638d6.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/librustc_std_workspace_core-3068aae2853ba0bc.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libcore-eb22ed92aa3586d1.rlib" "/home/luke/.rustup/toolchains/1.82-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-apple-darwin/lib/libcompiler_builtins-304a1afb7a72a7c7.rlib" "-liconv" "-lSystem" "-lc" "-lm" "-o" "/home/luke/maturin-zig/helloworld/target/x86_64-apple-darwin/release/deps/libhelloworld.dylib" "-Wl,-dead_strip" "-dynamiclib" "-Wl,-dylib" "-nodefaultlibs" "-undefined" "dynamic_lookup" "-Wl,-install_name,@rpath/helloworld.cpython-310-darwin.so"
  = note: error: unable to find dynamic system library 'iconv' using strategy 'paths_first'. searched paths: none
          error: unable to find dynamic system library 'charset' using strategy 'paths_first'. searched paths: none

I hope this helps figure out what happened between cargo-zigbuild / rust versions 🙂

[messense]

Seems like this is caused by rust-lang/rust#128370

[messense]

Fixed in main.