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contract C | |
{ | |
constructor() payable {} | |
function f(address payable a) public returns(bool) { | |
require(1000 == address(this).balance); | |
require(100 == a.balance); | |
a.send(600); | |
// a == this is not possible because address(this).balance == 1000 | |
// and a.balance == 100, | |
// so this should hold in CHC, ignoring the transfer revert. | |
return a.balance == 700; | |
} | |
} | |
contract D { | |
Forwarded immutable public f = new Forwarded(); | |
constructor() payable {} | |
receive() payable external { | |
// If `f` is not warm, then the call will go out of gas. | |
// Need to call warm_it_up or use access lists to fix this. | |
if (msg.value == 600) | |
address(f).call{value: 600, gas: 0}(""); | |
} | |
// Poor man's access list for warming up f | |
function warm_it_up() external { | |
address(f).call(""); | |
} | |
} | |
contract Forwarded { | |
receive() payable external { } | |
fallback() external {} | |
} | |
contract Test { | |
C immutable c = new C{value: 1000}(); | |
D immutable d = new D{value: 100}(); | |
constructor() payable {} | |
function test_with_warm() external returns (bool) { | |
// This makes the `call` in a.transfer(600) cost 100 gas. | |
// And `address(f).call{value: 600}("")` cost 100 gas | |
d.warm_it_up(); | |
return c.f(payable(d)); | |
} | |
function test_without_warming() external returns (bool) { | |
return c.f(payable(d)); | |
} | |
} | |
// ==== | |
// compileViaYul: also | |
// ---- | |
// constructor(), 1100 wei -> | |
// gas legacy: 542327 | |
// test_with_warm() -> false | |
// test_without_warming() -> false |
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