how we can do when compile meet Unknown Opcode?

I use the solidity compiler to compile a contract, and there are some "Unknown Opcode" in the bytecode. When I use evmjit to deploy the contract, it will go to the default branch whitch means it is "Invalid instruction - abort", and will stop the compile immediately. Should I remove the default branch and complete the compile? Is it OK?

Start by reproducing the Solidity compilation and evmjit deployment described in the issue, then inspect the default branch that handles an unknown opcode. Determine whether the opcode is valid for the targeted EVM version and document or test the intended behavior; the issue is done when unknown opcodes have an explicitly verified outcome.

Written by the indexing model from the issue text.