Fix USDT approval in cleanupErc20sViaCall using safeApproveWithRetry#58
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clemsos wants to merge 2 commits into
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Fix USDT approval in cleanupErc20sViaCall using safeApproveWithRetry#58clemsos wants to merge 2 commits into
clemsos wants to merge 2 commits into
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cleanupErc20sViaCall approved the call target with a typed IERC20(token).approve(to, amount). Mainnet USDT does not return a bool from approve(), so Solidity reverts when decoding the empty returndata, surfacing as EXECUTION_REVERTED and blocking gasless aUSDT -> mUSD conversions. Replace the typed approve with solady's safeApproveWithRetry, which tolerates tokens that do not return a bool on approve and resets the allowance to zero before re-approving a non-zero value (the second USDT quirk). All affected routers already declare 'using SafeTransferLib for address', so no new imports are required. Applies to the active v3 routers only; the deprecated v2.1 routers are left untouched. Refs: DEC-1106
Add mainnet-fork regression tests for the safeApproveWithRetry fix in cleanupErc20sViaCall, exercising both real USDT quirks against the live token and covering both changed v3 routers (tstore + non-tstore): - approve no longer reverts on USDT's missing bool return (the original EXECUTION_REVERTED that blocked gasless aUSDT -> mUSD) - the residual non-zero allowance path: when a target consumes less than the approved amount, the next cleanup re-approves over the residual without reverting (USDT's non-zero-over-non-zero approve guard) Also documents the root cause: a typed approve against real USDT reverts while decoding a bool from empty returndata. Refs: DEC-1106
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Summary
Replace the typed
IERC20.approve()call incleanupErc20sViaCallwith solady'ssafeApproveWithRetryto support non-standard ERC20 tokens like USDT.Key Changes
RelayRouterV3.solandRelayRouterV3_NonTstore.solto usetoken.safeApproveWithRetry(to, amount)instead ofIERC20(token).approve(to, amount)in thecleanupErc20sViaCallfunctionRelayRouterV3UsdtCleanupTest.sol) covering two USDT quirks:approvereturns no bool, causing typed calls to revert when decoding empty returndataImplementation Details
The fix addresses real-world compatibility issues with mainnet USDT (TetherToken):
safeApproveWithRetryhandles tokens that don't return a bool fromapproveThis resolves the EXECUTION_REVERTED error that previously blocked gasless aUSDT → mUSD transactions.
https://claude.ai/code/session_01Rh3tu7gX2ztgQMvSRbG5pX