function withdraw() external { if (false) { selfdestruct(payable(owner)); } // normal withdrawal logic } The optimizer removed the if (false) branch in bytecode entirely — or so I thought. Actually, the compiler preserved a JUMPDEST but no incoming JUMP opcode.
But there was a SSTORE in an admin function that allowed toggling a boolean flag — and that flag was used in another function to compute a jump offset via JUMPI . With a specific storage layout, that flag could point to the dead JUMPDEST . 0xdeadcode
One storage write to flip the false to true later, and pause becomes owner-only backdoor. With a specific storage layout, that flag could
When you compile a Solidity contract, the optimizer doesn't just remove unreachable paths — it buries them. But "unreachable" at compile time is not "unreachable at runtime" if the EVM state can change. But "unreachable" at compile time is not "unreachable
Last week I audited a contract with 14% unreachable instructions. The owner swore they were "leftover from testing."
I recently dissected a contract that had this:
It sounds like you're asking me to develop a post under the handle — likely for a platform like X (Twitter), a blog, GitHub, or a forum such as Ethereum Research or Stack Overflow.