Unable to use bit-vec third party crate

[mskd12]

I am unable to use the bit-vec crate inside the enclave. Here is what I am doing currently.

Cargo.toml:

bit-vec = { path = "../../../third_party/bit-vec"}

lib.rs:

extern crate bit_vec;

I am seeing the error below:

error: duplicate lang item in crate `std`: `f32_runtime`.
  |
  = note: first defined in crate `sgx_tstd`.

error: duplicate lang item in crate `std`: `f64_runtime`.
  |
  = note: first defined in crate `sgx_tstd`.

error: duplicate lang item in crate `std`: `panic_impl`.
  |
  = note: first defined in crate `sgx_tstd`.

error: duplicate lang item in crate `std`: `oom`.
  |
  = note: first defined in crate `sgx_trts`.

error: aborting due to 4 previous errors

error: Could not compile `dcnetenclave`.                                                                                                                                                                                                                                           

Please suggest how to fix/ workaround this bug.

[dingelish]

Hi @mskd12 ,

The above failure indicates that your dependencies bring std into the no_std environment. According to your usage of bit_vec, the default feature is enabled in your project. Thus bit-vec would depends on std::vec::Vec instead of alloc::vec::Vec. However, the default libstd cannot work together with sgx_tstd as std.

To solve this, there are two options:
(1) use xargo instead of cargo. In our sample projects, you can use XARGO_SGX=1 make to use xargo. Attention: please rustup component add rust-src and cargo install xargo.
(2) Disable the default feature of bit_vec, which would make it a no_std crate. Sample usage is either

[dependencies.bit-vec]
path = "../../third_party/bit-vec"
default-features = false

or

[dependencies]
bit-vec = { path = "../../third_party/bit-vec", default-features = false }

Then you could make which invoke cargo smoothly.
Best,
Yu