build: strip CBOR metadata footer for deterministic bytecode#106
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Set `bytecode_hash = "none"` in foundry.toml so emitted bytecode no longer contains the appended CBOR metadata block (IPFS source hash + solc version marker). The IPFS hash covers source paths and dependency layout, so the same source produced different bytes across clones — this churn polluted genesis.json regenerations without changing any runtime behavior. The `solc = "0.8.30"` pin above is what actually fixes the compiler version; the in-bytecode version marker was redundant artifact. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Summary
bytecode_hash = "none"infoundry.tomlso emitted bytecode no longer carries the appended CBOR metadata block (IPFS source hash + solc version marker).solc = "0.8.30"pin above is what actually fixes the compiler version; the in-bytecode version marker is just an artifact.Why
The IPFS hash in the CBOR footer is computed over a metadata JSON that includes source-file paths, dependency layout, and remapping serialization. The same source produced different bytes across clones /
node_moduleslayouts / machines, which polluted downstream consumers (most visibly:gravity_chain_core_contracts→gravity-mainnet-gitops/genesis.jsonregenerations would diff by hundreds of lines without any runtime behavior changing — see PR #110 on the gitops side for the empirical diagnosis).This change makes builds deterministic across clones, dependency layouts, OSes, and absolute-path differences.
What this changes
foundry.toml(solc = "0.8.30") is now the sole record of which solc was used.What this trades away
Test plan
forge clean && forge buildsucceeds.out/**/*.jsonartifact and confirmdeployedBytecode.objectno longer ends with thea26469706673...64736f6c63...0033CBOR footer.gravity-sdk/cluster/genesis.shagainst this ref twice from scratch and confirmgenesis.jsonis byte-identical both times.🤖 Generated with Claude Code