From dd285cdd5c7a8bbfecd882fef5db7522d6f29aba Mon Sep 17 00:00:00 2001
From: Joe Savona <joesavona@fb.com>
Date: Fri, 6 Jun 2025 09:56:04 -0700
Subject: [PATCH] Update base for Update on "[compiler] Repro for imprecise
 memo due to closure capturing changes"
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Syncing this stack internally there is a small percentage of files that lose memoization, generally for callbacks. The repro here tries to get at the core pattern, where a parameter escapes into a mutable return value. This makes the callback appear mutable, and means that calls like array.map aren't able to optimize as well — even if the array itself is transitively immutable.

The challenge is that we can't really distinguish between just capturing and true mutation right now — AnalyzeFunctions kind of has to pick one, and consider both a mutation.

[ghstack-poisoned]