[RULE] Rule G009: Detect Redundant Double Storage Writes (SSTORE)

[mijinummi]

Labels: medium-difficulty, gasguard-rules, static-analysis, gasguard
Difficulty: Medium
Module: rules/g009_redundant_sstore.rs

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🧠 Concept

Develop rule G009 to detect multiple writes (SSTORE) to the same storage variable within a single execution path before final state settlement.

⚠️ Problem

Updating a state variable multiple times within a single function call burns unnecessary gas when only the final state update needs to be persisted.

📁 Implementation Scope

• rules/g009_redundant_sstore.rs
• test/fixtures/g009_samples.sol

🛠️ Requirements

1. Analyze control flow graphs to track state variable assignments.
2. Flag cases where a variable is written, overridden, or updated multiple times prior to function exit without intermediate external reads.

🎯 Acceptance Criteria

• Successfully flags redundant state variable writes.
• Recommends holding intermediate values in stack variables prior to a single final SSTORE.

[amiramusa187-glitch]

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Hi, can I work on this please?

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[Malcolm-Wander]

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Hello maintainer,I’d love to work on this issue please,I promise to do a good and swift job..thank you.

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[devwums]

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Hi there, I'd like to contribute to this.

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Please assign this issue to me, I'd be happy to contribute.

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