While playing around with rustc 1.69.0-nightly (bd39bbb 2023-02-07) on MacOS, I ran into the following:

//const N: usize = 2_088_032; // largest size that works without abort const N: usize = 2_092_349; // first segfault  fn main () { let _ = Box::new([0; N]); }

With N <= 2088032 this program works fine; above that the binary that rustc makes produces a runtime abort. Both are acceptable outcomes.

But with N >= 2092349 running the program results in a segmentation fault instead. It sounds like something has destroyed something that the stack unwinder relies on?

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rustc --version --verbose:

rustc 1.69.0-nightly (bd39bbb4b 2023-02-07) binary: rustc commit-hash: bd39bbb4bb92df439bf6d85470e296cc6a47ffbd commit-date: 2023-02-07 host: aarch64-apple-darwin release: 1.69.0-nightly LLVM version: 15.0.7 

n/a (the compiled program segfaults)