Error when building contract with XCM.

[hbulgarini]

I'm trying to implement this xcm chain extension so we can put a simple contract that sends a XCM call.
The problem i'm facing is when i try to compile the contract with the given Cargo.toml, i get the following errors:

➜  ink git:(master) ✗ cargo +nightly contract build

....

error: the `#[global_allocator]` in ink_allocator conflicts with global allocator in: sp_io

error: duplicate lang item in crate `sp_io` (which `sp_application_crypto` depends on): `panic_impl`.
  |
  = note: the lang item is first defined in crate `ink_env` (which `flipper` depends on)
  = note: first definition in `ink_env` loaded from /Users/hectorb/blockchain/pallet-contracts-xcm/ink/target/ink/wasm32-unknown-unknown/release/deps/libink_env-0acca4fc7a95b368.rlib
  = note: second definition in `sp_io` loaded from /Users/hectorb/blockchain/pallet-contracts-xcm/ink/target/ink/wasm32-unknown-unknown/release/deps/libsp_io-7276ad9650247190.rlib, /Users/hectorb/blockchain/pallet-contracts-xcm/ink/target/ink/wasm32-unknown-unknown/release/deps/libsp_io-7276ad9650247190.rmeta

error: duplicate lang item in crate `sp_io` (which `sp_application_crypto` depends on): `oom`.
  |
  = note: the lang item is first defined in crate `ink_allocator` (which `ink_env` depends on)
  = note: first definition in `ink_allocator` loaded from /Users/hectorb/blockchain/pallet-contracts-xcm/ink/target/ink/wasm32-unknown-unknown/release/deps/libink_allocator-f7c621310e573610.rlib, /Users/hectorb/blockchain/pallet-contracts-xcm/ink/target/ink/wasm32-unknown-unknown/release/deps/libink_allocator-f7c621310e573610.rmeta
  = note: second definition in `sp_io` loaded from /Users/hectorb/blockchain/pallet-contracts-xcm/ink/target/ink/wasm32-unknown-unknown/release/deps/libsp_io-7276ad9650247190.rlib, /Users/hectorb/blockchain/pallet-contracts-xcm/ink/target/ink/wasm32-unknown-unknown/release/deps/libsp_io-7276ad9650247190.rmeta

error: could not compile `extension-xcm` due to 3 previous errors

Is there anything i'm not taking into account when building the contract? I have tried with many variants adding the xcm crate dependency from a new project using cargo contract new ..., but the error is the same.

Also it would be nice to know if there is there any working example of this extension where i can take references?

Thanks!

[hbulgarini]

it seems the contract compile using the following set up for xcm crate:

xcm = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "release-v0.9.25" }

after release .25, i start receiving the error again.

[dzmitry-lahoda]

confirming issue. on 9.0.25 works. on master or 0.9.32 same compilation issue.
i build it in separate cosmwasm(cosmos contract).

repo https://github.com/ComposableFi/composable/tree/dz/cosmwasm/xcm-executor/cosmwasm/contracts/xcm-executor

[dzmitry-lahoda]

needs upgrade to v3 paritytech/polkadot#6276 (comment)

[ashutoshvarma]

https://substrate.stackexchange.com/questions/4733/error-when-compiling-a-contract-using-the-xcm-chain-extension
Maybe closed this now