Linking errors when a project contains a binary and a library

[benruijl]

🐛 Bug Reports

Using the minimal setup below, which contains a main.rs and a lib.rs, I get the following linker error:

error: linking with `cc` failed: exit code: 1
  |
  = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-m64" "-L" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "/home/ben/pythonapi/target/debug/deps/bar-1cd5931f960d78ef.2364k5u36xjw4mn8.rcgu.o" "/home/ben/pythonapi/target/debug/deps/bar-1cd5931f960d78ef.3wp0zm2gkkx6swv8.rcgu.o" "/home/ben/pythonapi/target/debug/deps/bar-1cd5931f960d78ef.46822g7yvqxpgt2s.rcgu.o" "/home/ben/pythonapi/target/debug/deps/bar-1cd5931f960d78ef.4zg4tmuhj52ks96w.rcgu.o" "/home/ben/pythonapi/target/debug/deps/bar-1cd5931f960d78ef.vkoh5x8xi1cexdw.rcgu.o" "-o" "/home/ben/pythonapi/target/debug/deps/bar-1cd5931f960d78ef" "/home/ben/pythonapi/target/debug/deps/bar-1cd5931f960d78ef.1y7gc8l4weaej8o9.rcgu.o" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-Wl,-znow" "-nodefaultlibs" "-L" "/home/ben/pythonapi/target/debug/deps" "-L" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/home/ben/pythonapi/target/debug/deps/libbar-20b4232cfeb2e343.rlib" "/home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib" "/home/ben/pythonapi/target/debug/deps/libparking_lot-80ea636726af17a2.rlib" "/home/ben/pythonapi/target/debug/deps/libparking_lot_core-28df18bc562f242a.rlib" "/home/ben/pythonapi/target/debug/deps/libsmallvec-fb9d0a06a85a61af.rlib" "/home/ben/pythonapi/target/debug/deps/libcfg_if-ab1bd98be96b57b3.rlib" "/home/ben/pythonapi/target/debug/deps/liblock_api-670d43905d10a659.rlib" "/home/ben/pythonapi/target/debug/deps/libscopeguard-c8e12dbcd597c2e4.rlib" "/home/ben/pythonapi/target/debug/deps/libinstant-5a5c9b71ee271cc2.rlib" "/home/ben/pythonapi/target/debug/deps/liblibc-809b3ff95751964d.rlib" "/home/ben/pythonapi/target/debug/deps/libunindent-b569d19c5d9fcd61.rlib" "/home/ben/pythonapi/target/debug/deps/libpaste-8d6803f4aa113c0d.rlib" "/home/ben/pythonapi/target/debug/deps/libinventory-9412637833a73b14.rlib" "/home/ben/pythonapi/target/debug/deps/libindoc-734b491b84a0d49a.rlib" "-Wl,--start-group" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-8bb11f807a7b6b4c.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-ca8087507780d964.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-259c92b387c1c166.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-16e0a2fbbb8e14b3.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libbacktrace-8a1651b8e23d2aaf.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libbacktrace_sys-23bdd98b0574083e.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-855a92055ec33e2e.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-24c70dd44fbacdfb.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcfg_if-b326273841bae587.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-ac3c1f0e16507051.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-a5729542b65954aa.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-09bd1119ab1cad7d.rlib" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-9a787681bfbeaf61.rlib" "-Wl,--end-group" "/home/ben/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-5a0398ee67f74664.rlib" "-Wl,-Bdynamic" "-lutil" "-ldl" "-lutil" "-ldl" "-lrt" "-lpthread" "-lgcc_s" "-lc" "-lm" "-lrt" "-lpthread" "-lutil" "-ldl" "-lutil"
  = note: /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libbar-20b4232cfeb2e343.rlib(bar-20b4232cfeb2e343.pwt7b75ceqh6rgt.rcgu.o): in function `pyo3::err::PyErr::restore':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/err.rs:371: undefined reference to `PyErr_Restore'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libbar-20b4232cfeb2e343.rlib(bar-20b4232cfeb2e343.wjxnm2eusla6pko.rcgu.o): in function `pyo3::types::tuple::<impl pyo3::conversion::ToPyObject for (A,)>::to_object':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/types/tuple.rs:151: undefined reference to `PyTuple_New'
          /usr/bin/ld: /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/types/tuple.rs:152: undefined reference to `PyTuple_SetItem'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libbar-20b4232cfeb2e343.rlib(bar-20b4232cfeb2e343.1b5kxnlpjv73af4c.rcgu.o): in function `pyo3::types::tuple::<impl pyo3::conversion::ToPyObject for (A,)>::to_object':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/types/tuple.rs:151: undefined reference to `PyTuple_New'
          /usr/bin/ld: /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/types/tuple.rs:152: undefined reference to `PyTuple_SetItem'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libbar-20b4232cfeb2e343.rlib(bar-20b4232cfeb2e343.3kavbq3o9ru1tgyk.rcgu.o): in function `<pyo3::types::any::PyAny as pyo3::type_object::PyTypeInfo>::type_object_raw':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/types/mod.rs:147: undefined reference to `PyBaseObject_Type'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libbar-20b4232cfeb2e343.rlib(bar-20b4232cfeb2e343.3smrrh9783l6qj2r.rcgu.o): in function `pyo3::pyclass::default_new':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/pyclass.rs:(.text._ZN4pyo37pyclass11default_new17h53bf5ca33b236b33E+0xaa): undefined reference to `PyType_GenericAlloc'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.0.rcgu.o): in function `pyo3::err::PyErr::fetch':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/err.rs:189: undefined reference to `PyErr_Fetch'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.0.rcgu.o): in function `pyo3::err::PyErr::new_type':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/err.rs:236: undefined reference to `PyErr_NewException'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.0.rcgu.o): in function `pyo3::err::PyErr::print':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/err.rs:275: undefined reference to `PyErr_PrintEx'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.0.rcgu.o): in function `pyo3::err::PyErr::restore':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/err.rs:371: undefined reference to `PyErr_Restore'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.0.rcgu.o): in function `pyo3::err::panic_after_error':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/err.rs:578: undefined reference to `PyErr_Print'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.10.rcgu.o): in function `pyo3::types::string::PyString::new':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/types/string.rs:28: undefined reference to `PyUnicode_FromStringAndSize'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.10.rcgu.o): in function `pyo3::types::string::PyString::as_bytes':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/types/string.rs:50: undefined reference to `PyUnicode_AsUTF8AndSize'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.13.rcgu.o): in function `pyo3::ffi::object::Py_DECREF':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/ffi/object.rs:945: undefined reference to `_Py_Dealloc'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.13.rcgu.o): in function `pyo3::ffi::object::Py_None':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/ffi/object.rs:987: undefined reference to `_Py_NoneStruct'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.7.rcgu.o): in function `pyo3::gil::prepare_freethreaded_python::{{closure}}':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/gil.rs:84: undefined reference to `Py_IsInitialized'
          /usr/bin/ld: /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/gil.rs:103: undefined reference to `Py_InitializeEx'
          /usr/bin/ld: /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/gil.rs:126: undefined reference to `PyEval_SaveThread'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.7.rcgu.o): in function `pyo3::gil::prepare_freethreaded_python::{{closure}}::finalize':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/gil.rs:108: undefined reference to `Py_IsInitialized'
          /usr/bin/ld: /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/gil.rs:109: undefined reference to `PyGILState_Ensure'
          /usr/bin/ld: /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/gil.rs:110: undefined reference to `Py_Finalize'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.7.rcgu.o): in function `pyo3::gil::GILGuard::acquire':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/gil.rs:163: undefined reference to `PyGILState_Ensure'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.7.rcgu.o): in function `<pyo3::gil::GILGuard as core::ops::drop::Drop>::drop':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/gil.rs:193: undefined reference to `PyGILState_Release'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.9.rcgu.o): in function `<pyo3::exceptions::BaseException as pyo3::type_object::PyTypeObject>::type_object':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/exceptions.rs:223: undefined reference to `PyExc_BaseException'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.9.rcgu.o): in function `<pyo3::exceptions::SystemError as pyo3::type_object::PyTypeObject>::type_object':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/exceptions.rs:223: undefined reference to `PyExc_SystemError'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.9.rcgu.o): in function `<pyo3::exceptions::TypeError as pyo3::type_object::PyTypeObject>::type_object':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/exceptions.rs:223: undefined reference to `PyExc_TypeError'
          /usr/bin/ld: /home/ben/pythonapi/target/debug/deps/libpyo3-9f8b2bfa83998ca0.rlib(pyo3-9f8b2bfa83998ca0.pyo3.dfhfqc1n-cgu.9.rcgu.o): in function `<pyo3::exceptions::UnicodeDecodeError as pyo3::type_object::PyTypeObject>::type_object':
          /home/ben/.cargo/registry/src/github.com-1ecc6299db9ec823/pyo3-0.11.1/src/exceptions.rs:223: undefined reference to `PyExc_UnicodeDecodeError'
          collect2: error: ld returned 1 exit status
          

🌍 Environment

• Your operating system and version: Arch Linux
• Your python version: 3.8.5
• How did you install python (e.g. apt or pyenv)? Did you use a virtualenv?: pacman
• Your Rust version (rustc --version): 1.45.2
• Your PyO3 version: 0.11.1
• Have you tried using latest PyO3 master (replace version = "0.x.y" with git = "https://github.com/PyO3/pyo3")?: yes

💥 Reproducing

cargo.toml

[package]
edition = "2018"
name = "bar"
version = "0.1.0"

[dependencies.pyo3]
features = ["extension-module"]
version = "0.11.1"

[lib]
crate-type = ["lib"]
name = "bar"

lib.rs:

use pyo3::prelude::*;

pub struct Foo {}

impl Foo {
    pub fn a() -> Foo {
        Foo {}
    }
}

#[pyclass]
struct SomePython {}

#[pymethods]
impl SomePython {
    #[new]
    fn new() -> SomePython {
        SomePython {}
    }
}

main.rs:

use bar::Foo;

fn main() {
    Foo::a();
}

[davidhewitt]

Unfortunately this is our extension-module feature causing issues. Please see this FAQ entry which has a workaround for cargo test; you'll have to use this workaround when building the binary.

We're actively prototyping ways to make this API better to use. See e.g. #1040

[rookboom]

I get the same error, but managed to solve it with the workaround...

foo_lib

Cargo.toml

[package]
name = "foo_lib"
version = "0.1.0"
edition = "2021"

[dependencies]
pyo3 = "^0.15"

[features]
default = ["pyo3/extension-module"]

foo_bin

Cargo.toml

[package]
name = "foo_bin"
version = "0.1.0"
edition = "2021"


[dependencies]
foo_lib = {path = "../foo_lib", default-features = false}
pyo3 = "^0.15"

foo.zip

cargo run results in the same error above. cargo run --no-default-features works though.