contract C { bytes public initCode; constructor() { // This should catch problems, but lets also test the case the optimiser is buggy. assert(address(this).code.length == 0); initCode = address(this).code; } // To avoid dependency on exact length. function f() public view returns (bool) { return address(this).code.length > 400; } function g() public view returns (uint) { return address(0).code.length; } function h() public view returns (uint) { return address(1).code.length; } } // ---- // constructor() -> // gas irOptimized: 172853 // gas legacy: 241796 // gas legacyOptimized: 153454 // initCode() -> 0x20, 0 // f() -> true // g() -> 0 // h() -> 0