From 6b1ea96b9404ccfc8e66e22fa2a7b645781255c3 Mon Sep 17 00:00:00 2001
From: Gabriela Araujo Britto <gabrielaa@microsoft.com>
Date: Wed, 4 Dec 2024 09:13:13 -0800
Subject: [PATCH] Fix flow node improper reuse (#60662)

---
 src/compiler/binder.ts                              |  4 ++++
 .../fourslash/unreachableStatementNodeReuse.ts      | 13 +++++++++++++
 2 files changed, 17 insertions(+)
 create mode 100644 tests/cases/fourslash/unreachableStatementNodeReuse.ts

diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index b071f72b712c2..41966df6672e9 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -21,6 +21,7 @@ import {
     BreakOrContinueStatement,
     CallChain,
     CallExpression,
+    canHaveFlowNode,
     canHaveLocals,
     canHaveSymbol,
     CaseBlock,
@@ -1104,6 +1105,9 @@ function createBinder(): (file: SourceFile, options: CompilerOptions) => void {
         // and set it before we descend into nodes that could actually be part of an assignment pattern.
         inAssignmentPattern = false;
         if (checkUnreachable(node)) {
+            if (canHaveFlowNode(node) && node.flowNode) {
+                node.flowNode = undefined;
+            }
             bindEachChild(node);
             bindJSDoc(node);
             inAssignmentPattern = saveInAssignmentPattern;
diff --git a/tests/cases/fourslash/unreachableStatementNodeReuse.ts b/tests/cases/fourslash/unreachableStatementNodeReuse.ts
new file mode 100644
index 0000000000000..9ede6fd059c95
--- /dev/null
+++ b/tests/cases/fourslash/unreachableStatementNodeReuse.ts
@@ -0,0 +1,13 @@
+/// <reference path="fourslash.ts" />
+
+//// function test() {
+//// 	return/*a*/abc();
+//// 	return;
+//// }
+//// function abc() { }
+
+verify.numberOfErrorsInCurrentFile(1);
+
+goTo.marker("a")
+edit.insert(" ");
+verify.noErrors();
\ No newline at end of file