fix(forge): prevent gas underflow in delete operations on Cancun #12861
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subwaycookiecrunch
requested review from
DaniPopes,
grandizzy,
mattsse and
zerosnacks
as code owners
subwaycookiecrunch
requested review from
0xrusowsky and
onbjerg
as code owners
DaniPopes
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Dec 17, 2025
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Thanks for the feedback
I agree that saturating_sub may mask incorrect gas accounting.
Would you prefer:
- an explicit fork-check (Cancun vs Prague), or
- guarding the subtraction with a conditional + debug assertion, or
- returning early when gas < stipend inside pauseGasMetering?
Happy to rework this to preserve gas semantics while avoiding the panic.
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Fixes a gas underflow issue that occurs when using
deleteoperations within apauseGasMeteringblock on the Cancun EVM version.In Cancun, the reported gas usage can drop below the stipend due to the absence of the EIP-7702 gas floor (unlike in Prague). This previously triggered a wrapping subtraction panic in the test runner's gas calculation.
This PR replaces the wrapping subtraction with a saturating subtraction to correctly handle this scenario, ensuring that gas usage is reported as 0 rather than underflowing to a large integer.
Fixes #12803
Verified with a new regression test in
repros.rs.