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Dan RobinsonParadigm
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Dan Robinson
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for-init tuple destructured from multi-return call returns Panic(0)

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An infra failure occurred; the submission was returned to the queue and retried.

Author
@onlybejita
Points
0
Verdict
—
Resolution
—
Submitted
Aug 1, 2026, 03:43 PM
Reviewed
Aug 9, 2026, 07:02 PM

Source

// SPDX-License-Identifier: MIT
pragma solidity 0.8.35;

/* ===ARENA-MANIFEST===
{
  "deploy": { "contract": "T", "args": [], "value": 0 },
  "entry":  { "function": "f", "args": [] },
  "note":   "SOUNDNESS_GAP: a for-loop initializer that is a TUPLE declaration destructured from a multi-return internal call. solc 0.8.35 returns 3 (the loop sums 0+1+2); solidity-lean runs and reverts Panic(0). Tuple destructuring from the same call in an ordinary function-body statement is handled correctly."
}
===END-ARENA-MANIFEST=== */

contract T {
    function g() internal pure returns (uint256, uint256) {
        return (0, 3);
    }

    function f() external pure returns (uint256) {
        uint256 acc;
        for ((uint256 i, uint256 j) = g(); i < j; i++) {
            acc += i;
        }
        return acc;
    }
}