Looks like none of C++ code generated is linked properly

[BlueZeeKing]

When running cargo build, I get the error message:

   Compiling ctre v0.1.0 (/Users/braydenzee/Desktop/robotrs/ctre)
warning: unused variable: `motor`
  --> ctre/src/main.rs:36:9
   |
36 |     let motor = ffi::new_VictorSPX(1);
   |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_motor`
   |
   = note: `#[warn(unused_variables)]` on by default

error: linking with `arm-frc2023-linux-gnueabi-gcc` failed: exit status: 1
  |
  = note: LC_ALL="C" PATH="<MY PATH>" VSLANG="1033" "arm-frc2023-linux-gnueabi-gcc" "/var/folders/wg/qnccs2s93hq87y4v80s6dfdc0000gn/T/rustcMXlkXt/symbols.o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.14zj3412z7hn0mq4.rcgu.o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.1o2enzafrkhtj0xr.rcgu.o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.1x6s0wz0jwzspqlo.rcgu.o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.2629p3efs6y22dw3.rcgu.o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.351r58jm1tus3hek.rcgu.o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.3qp63jav4qoo4sqx.rcgu.o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.47uhe5vft99u93un.rcgu.o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.2thq35rbcx7h6414.rcgu.o" "-Wl,--as-needed" "-L" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps" "-L" "/Users/braydenzee/Desktop/robotrs/target/debug/deps" "-L" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/build/ctre-d654242bc31a2273/out/lib" "-L" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/build/ctre-d654242bc31a2273/out" "-L" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/build/cxx-97f482b489ef9637/out" "-L" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/build/link-cplusplus-106c66522b413248/out" "-L" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib" "-Wl,-Bstatic" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/libcxx-cba368c3337febe2.rlib" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/liblink_cplusplus-0de2200d69ca588c.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libstd-ae6c1ab5c02c448e.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libpanic_unwind-4efcc033e29e3a60.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libobject-84b151303bbd2cd1.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libmemchr-9f4c7a5ddeb7f6c9.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libaddr2line-dcd97406b7431b1e.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libgimli-be9185e9796719e2.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/librustc_demangle-862301a10afbf865.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libstd_detect-e8cdac7dbe7c977e.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libhashbrown-5685716dc6e2099a.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/librustc_std_workspace_alloc-aca6c7e4ac6ddd6f.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libminiz_oxide-6495e44664ebde64.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libadler-03530f9a78709cc6.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libunwind-cd5793ef2d0bbab7.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libcfg_if-8f091c3035e12743.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/liblibc-244a7eee40908a43.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/liballoc-780f7c19e4f567bd.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/librustc_std_workspace_core-5be79fcb582be8f8.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libcore-7973391c065a5459.rlib" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib/libcompiler_builtins-1d96fdf42bdaa657.rlib" "-Wl,-Bdynamic" "-lstdc++" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "/Users/braydenzee/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/arm-unknown-linux-gnueabi/lib" "-o" "/Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs"
  = note: /Users/braydenzee/.gradle/toolchains/frc/2023/roborio/bin/../arm-nilrt-linux-gnueabi/sysroot/usr/lib/gcc/arm-nilrt-linux-gnueabi/12/../../../../../../../arm-nilrt-linux-gnueabi/bin/ld: /Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.14zj3412z7hn0mq4.rcgu.o: in function `ctre::ffi::new_VictorSPX':
          /Users/braydenzee/Desktop/robotrs/ctre/src/main.rs:11: undefined reference to `cxxbridge1$new_VictorSPX'
          /Users/braydenzee/.gradle/toolchains/frc/2023/roborio/bin/../arm-nilrt-linux-gnueabi/sysroot/usr/lib/gcc/arm-nilrt-linux-gnueabi/12/../../../../../../../arm-nilrt-linux-gnueabi/bin/ld: /Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.14zj3412z7hn0mq4.rcgu.o: in function `<ctre::ffi::VictorSPX as cxx::unique_ptr::UniquePtrTarget>::__raw':
          /Users/braydenzee/Desktop/robotrs/ctre/src/main.rs:11: undefined reference to `cxxbridge1$unique_ptr$ctre$phoenix$motorcontrol$can$VictorSPX$raw'
          /Users/braydenzee/.gradle/toolchains/frc/2023/roborio/bin/../arm-nilrt-linux-gnueabi/sysroot/usr/lib/gcc/arm-nilrt-linux-gnueabi/12/../../../../../../../arm-nilrt-linux-gnueabi/bin/ld: /Users/braydenzee/Desktop/robotrs/target/arm-unknown-linux-gnueabi/debug/deps/ctre-780ae51c3efcc338.14zj3412z7hn0mq4.rcgu.o: in function `<ctre::ffi::VictorSPX as cxx::unique_ptr::UniquePtrTarget>::__drop':
          /Users/braydenzee/Desktop/robotrs/ctre/src/main.rs:11: undefined reference to `cxxbridge1$unique_ptr$ctre$phoenix$motorcontrol$can$VictorSPX$drop'
          collect2: error: ld returned 1 exit status
          
  = note: some `extern` functions couldn't be found; some native libraries may need to be installed or have their path specified
  = note: use the `-l` flag to specify native libraries to link
  = note: use the `cargo:rustc-link-lib` directive to specify the native libraries to link with Cargo (see https://doc.rust-lang.org/cargo/reference/build-scripts.html#cargorustc-link-libkindname)

warning: `ctre` (bin "ctre") generated 1 warning
error: could not compile `ctre` (bin "ctre") due to previous error; 1 warning emitted

This compiled for a cortex A9 chip running linux from an Apple M1 laptop running macos. I assume there is something I'm missing but I can't figure out what.

[BlueZeeKing]

I just tested the demo compiling for x86_64 linux from the same computer and that also didn't work. Does cxx simply not work when cross compiling?

[ray1422]

same issue

undefined symbol: cxxbridge1$unique_ptr$[my class]$raw

[evbo]

So how is anyone using this repo if it can't link properly? Does it only pertain to gcc, where order of linking matters? Should we be using a different c++ compiler?

Here's me trying to compile the last step of the demo with linking errors: #1448