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  "path": "/t/how-do-you-handle-tricky-ffi-memory-safety-issues-in-production/24338#post_1",
  "publishedAt": "2026-05-18T02:16:20.000Z",
  "site": "https://internals.rust-lang.org",
  "textContent": "Hi Everyone～ I'm a Rust developer based in East Asia. I've been repeatedly bitten by FFI-related bugs — the kind that only appear at 2 AM in production. As soon as code crosses extern \"C\", the borrow checker becomes useless, and problems like ownership violations, lifetime mismatches, double-frees, and pointer escapes become extremely difficult to catch.\n\nI'm getting tired of debugging these the hard way, so I'm seriously considering building a tool to help solve this problem — specifically something that can analyze LLVM IR to track pointer lifetimes and data flow across language boundaries (Rust ↔ C/C++ ↔ Zig, etc.).\n\nBefore I invest a lot of time into it, I'd love to hear from the community:\n\n  * What are the worst or most common FFI / unsafe memory safety bugs you've encountered in real projects?\n  * What tools or techniques are you currently using to catch these kinds of issues? (Miri, cargo-audit, manual review, static analyzers, etc.)\n  * If a new tool were to be built for this, what features or pain points would you actually want it to address?\n  * Any reasons why this kind of LLVM IR level approach might be a bad idea?\n\n\n\nAny real-world advice, war stories, or brutal feedback would be super helpful. Thank you!",
  "title": "How do you handle tricky FFI memory safety issues in production?"
}