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diff --git a/src/mongo/db/exec/requires_index_stage.cpp b/src/mongo/db/exec/requires_index_stage.cpp
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+++ b/src/mongo/db/exec/requires_index_stage.cpp
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+/**
+ *    Copyright (C) 2018-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/db/exec/requires_index_stage.h"
+
+namespace mongo {
+
+void RequiresIndexStage::doSaveStateRequiresCollection() {
+    doSaveStateRequiresIndex();
+
+    // During yield, we relinquish our shared ownership of the index catalog entry. This allows the
+    // index to be dropped during yield, but permits us to check via the weak_ptr interface
+    // whether the index is still valid on yield recovery.
+    //
+    // We also set catalog pointers to null, since accessing these pointers is illegal during yield.
+    _indexCatalogEntry.reset();
+    _indexDescriptor = nullptr;
+    _indexAccessMethod = nullptr;
+}
+
+void RequiresIndexStage::doRestoreStateRequiresCollection() {
+    // Reacquire shared ownership of the index catalog entry. If we're unable to do so, then the
+    // our index is no longer valid, and the query should die.
+    _indexCatalogEntry = _weakIndexCatalogEntry.lock();
+    uassert(ErrorCodes::QueryPlanKilled,
+            str::stream() << "query plan killed :: index named '" << _indexName
+                          << "' is no longer valid",
+            _indexCatalogEntry);
+
+    _indexDescriptor = _indexCatalogEntry->descriptor();
+    _indexAccessMethod = _indexCatalogEntry->accessMethod();
+
+    doRestoreStateRequiresIndex();
+}
+
+}  // namespace mongo