diff --git a/clang-tools-extra/clangd/ClangdLSPServer.cpp b/clang-tools-extra/clangd/ClangdLSPServer.cpp
--- a/clang-tools-extra/clangd/ClangdLSPServer.cpp
+++ b/clang-tools-extra/clangd/ClangdLSPServer.cpp
@@ -371,16 +371,6 @@
 
   llvm::StringMap<std::function<void(llvm::json::Value)>> Notifications;
   llvm::StringMap<std::function<void(llvm::json::Value, ReplyOnce)>> Calls;
-  // The maximum number of callbacks held in clangd.
-  //
-  // We bound the maximum size to the pending map to prevent memory leakage
-  // for cases where LSP clients don't reply for the request.
-  static constexpr int MaxReplayCallbacks = 100;
-  mutable std::mutex CallMutex;
-  int NextCallID = 0; /* GUARDED_BY(CallMutex) */
-  std::deque<std::pair</*RequestID*/ int,
-                       /*ReplyHandler*/ Callback<llvm::json::Value>>>
-      ReplyCallbacks; /* GUARDED_BY(CallMutex) */
 
   // Method calls may be cancelled by ID, so keep track of their state.
   // This needs a mutex: handlers may finish on a different thread, and that's
@@ -432,6 +422,19 @@
     }));
   }
 
+  // The maximum number of callbacks held in clangd.
+  //
+  // We bound the maximum size to the pending map to prevent memory leakage
+  // for cases where LSP clients don't reply for the request.
+  // This has to go after RequestCancellers and RequestCancellersMutex since it
+  // can contain a callback that has a cancelable context.
+  static constexpr int MaxReplayCallbacks = 100;
+  mutable std::mutex CallMutex;
+  int NextCallID = 0; /* GUARDED_BY(CallMutex) */
+  std::deque<std::pair</*RequestID*/ int,
+                       /*ReplyHandler*/ Callback<llvm::json::Value>>>
+      ReplyCallbacks; /* GUARDED_BY(CallMutex) */
+
   ClangdLSPServer &Server;
 };
 constexpr int ClangdLSPServer::MessageHandler::MaxReplayCallbacks;