Unsupported EVM Features

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E3001: UnsupportedFeature

error[E3001]: unsupported feature: delegatecall
  --> MyContract.sol:15:9
   |
15 |         address(impl).delegatecall(data);
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: NeoVM has no delegate call mechanism
   = help: use ContractManagement.update() for upgradeable contracts

Blocked or limited constructs and their Neo alternatives:

Feature / construct	Diagnostic	Neo Alternative
delegatecall	E3001	ContractManagement.update() for upgrades
Unsupported Yul inside assembly	Warning	Use Solidity or devpack libraries instead
EVM CREATE / CREATE2 opcodes	E3001	ContractManagement.deploy(...)

WARNING

delegatecall and EVM create opcodes have no safe 1:1 NeoVM equivalent. Inline assembly has limited Yul lowering, but EVM-only operations inside it still need Neo-native replacements. Solidity new Contract(...) is not real deployment on Neo: the compiler currently inlines/simulates constructor-like logic and returns a zero-address placeholder. type(X).creationCode and type(X).runtimeCode are not blocked; they compile to deterministic Neo-shaped compatibility payloads for hashing, not deployable EVM bytecode.

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