I agree that could happen, but a parser would have to be coded pretty strangely to disable these basic ARC optimizations. I don't imagine a parser needing to ho

I agree that could happen, but a parser would have to be coded pretty strangely to disable these basic ARC optimizations. I don't imagine a parser needing to hold and release references beyond the call stack. In this vein, both Swift and Rust performance will succumb to any number of their IL-level (and LLVM's IR-level) optimizations being disabled by some seemingly orthogonal change to the source code. Either way, I hope Apple (and others) can squash this entire category of bugs soon!