From b4178af81b02dfa0e898670ce564c4649fd8947f Mon Sep 17 00:00:00 2001
From: Paul Shen <paulshen0@gmail.com>
Date: Wed, 17 Jul 2019 17:21:19 -0700
Subject: [PATCH] clean up nextEffect pointers (#16115)

---
 .../react-reconciler/src/ReactFiberWorkLoop.js    | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/packages/react-reconciler/src/ReactFiberWorkLoop.js b/packages/react-reconciler/src/ReactFiberWorkLoop.js
index 1c291d0b87..510f31c2b5 100644
--- a/packages/react-reconciler/src/ReactFiberWorkLoop.js
+++ b/packages/react-reconciler/src/ReactFiberWorkLoop.js
@@ -1712,6 +1712,16 @@ function commitRootImpl(root) {
     rootDoesHavePassiveEffects = false;
     rootWithPendingPassiveEffects = root;
     pendingPassiveEffectsExpirationTime = expirationTime;
+  } else {
+    // We are done with the effect chain at this point so let's clear the
+    // nextEffect pointers to assist with GC. If we have passive effects, we'll
+    // clear this in flushPassiveEffects.
+    nextEffect = firstEffect;
+    while (nextEffect !== null) {
+      const nextNextEffect = nextEffect.nextEffect;
+      nextEffect.nextEffect = null;
+      nextEffect = nextNextEffect;
+    }
   }
 
   // Check if there's remaining work on this root
@@ -1947,7 +1957,10 @@ export function flushPassiveEffects() {
         captureCommitPhaseError(effect, error);
       }
     }
-    effect = effect.nextEffect;
+    const nextNextEffect = effect.nextEffect;
+    // Remove nextEffect pointer to assist GC
+    effect.nextEffect = null;
+    effect = nextNextEffect;
   }
 
   if (enableSchedulerTracing) {