Delegatecall forwarder with a hardcoded implementation and a literal failure jump.
Historical Significance
Deployed long before the minimal proxy standard was written down, using old style inline assembly labels. The hardcoded jump offset is a latent bug that is unreachable in normal operation, which is how it survived a very large deployment run without being noticed.
Key Facts
Description
A compact proxy whose payable fallback copies incoming calldata into memory and delegatecalls a fixed implementation address, forwarding most of the remaining gas and returning a single 32 byte word. The delegatecall failure branch jumps to a hardcoded offset rather than the invalid opcode stub, so it lands in the implementation getter's epilogue. The executable code is identical to another group deployed against the same implementation, and only the source metadata hash differs, so the two were compiled from source files that varied in comments or whitespace alone. The runtime code matches the deployed bytecode byte for byte. Only the trailing swarm metadata hash differs, because the EthereumHistory attribution comment changes the source text. Sourcify records this as a partial match and Etherscan shows it as verified.
Source Verified
Bytecode Overview
Verified Source Available
Source verified through compiler archaeology and exact bytecode matching.
View Verification ProofShow source code (Solidity)
// Submitted by EthereumHistory (ethereumhistory.com)
pragma solidity ^0.4.11;
contract Proxy {
function implementation() internal constant returns (address) {
return 0xc3b2ae46792547a96b9f84405e36d0e07edcd05c;
}
function () payable {
address target = implementation();
assembly {
let ptr := msize()
mstore(0x40, add(ptr, calldatasize))
calldatacopy(ptr, 0, calldatasize)
jumpi(0x54, iszero(delegatecall(div(mul(gas, 0x3f), 0x40), target, ptr, calldatasize, 0, 0x20)))
return(0, 0x20)
fail:
invalid
}
}
}