Different results depending on architecture

[bksaiki]

Based on failing tests in Herbie, different architectures actually create different results, specifically Ubuntu 24.04 on x86 and MacOS 14.5 on arm64 (both with Rust version 1.80). Created a unit test to run with the same expressions and rules. Used GitHub Actions to run on multiple platforms.

Reproduce:

• checkout Herbie at nondeterminism
• in egg-herbie/ run RUST_LOG=info cargo test --release --package egg-herbie --lib -- bug::repro --nocapture

(h/t @zaneenders for the find)

[mwillsey]

@bksaiki is this still true?

[bksaiki]

Just tested using main. It's still happening. I'm running some rules on an initial egraph here. The last lines of the log are different.

macOS 14.7.2, aarch64: log
macOS 13.7.2, x64: log