cargo concordium build
Finished release [optimized] target(s) in 0.01s
Error: Could not build smart contract.
Caused by:
0: Could not validate resulting smart contract module as a V1 contract.
1: Unsupported instruction 0xc0
I have changed the concordium-std & concordium-cis2 dependencies versions have not changed.
also cargo concordium version (2.7.0) is not changed
Even the cis2-multi example from the official repo throws this error upon building
Newer versions (v. 1.70 onwards) of rust use some wasm instructions we do not currently support in the smart contracts. So for the moment you will need to build contracts using an older version e.g. 1.69.