Security Warnings (E5xxx)

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Code	Name	Description	Recommendation
E5001	ReentrancyRisk	Potential reentrancy vulnerability	Use checks-effects-interactions pattern
E5002	UncheckedCall	Unchecked external call	Check return value of external calls
E5003	TxOriginUsage	tx.origin used for authorization	Use msg.sender instead
E5004	UnsafeDelegate	Unsafe delegatecall	delegatecall is blocked on NeoVM; refactor
E5005	IntegerOverflowRisk	Potential integer overflow	Use SafeMath or Solidity 0.8.x checked arithmetic

WARNING

Security warnings (E5xxx) should be treated as errors in production builds. Use --Werror E5 to enforce this in your CI pipeline.

Example: E5001 ReentrancyRisk

warning[E5001]: potential reentrancy vulnerability in function 'withdraw'
  --> MyContract.sol:20:5
   |
20 |     payable(msg.sender).transfer(balance);
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: move state changes before external calls (checks-effects-interactions pattern)

Fix: Reorder operations so state changes happen before external calls:

// Before (vulnerable)
function withdraw() public {
    uint256 balance = balances[msg.sender];
    payable(msg.sender).transfer(balance);  // external call first
    balances[msg.sender] = 0;               // state change after
}

// After (safe)
function withdraw() public {
    uint256 balance = balances[msg.sender];
    balances[msg.sender] = 0;               // state change first
    payable(msg.sender).transfer(balance);  // external call after
}