---
id: 1787
title: "Part 1: The life of an optimization barrier"
source_domain: blog.trailofbits.com
source_url: "https://blog.trailofbits.com/2022/01/26/part-1-the-life-of-an-optimization-barrier/"
published_at: "2022-01-26T12:00:35Z"
tags: ["rust", "cryptography", "llvm", "constant-time", "side-channels", "webassembly"]
phying_url: "https://phying.com/item/1787"
lang: en
---

# Part 1: The life of an optimization barrier

## Summary

Constant-time Rust cryptography can be broken by optimization. Compiling to WebAssembly means code passes through two optimizers, and LLVM itself may introduce a new timing side-channel.

## Intelligence Metadata

- **Sources:** blog.trailofbits.com
- **Published:** 2022-01-26T12:00:35Z
- **Original:** https://blog.trailofbits.com/2022/01/26/part-1-the-life-of-an-optimization-barrier/
- **Phying News:** https://phying.com/item/1787