good

command_line.cc

@@ -21,6 +21,11 @@
 #include <fcntl.h>
 #endif
 
+const char* kIpcIndexerName = "indexer";
+const char* kIpcLanguageClientName = "language_client";
+
+const int kNumIndexers = 8 - 1;
+
 std::unordered_map<std::string, std::string> ParseOptions(int argc, char** argv) {
   std::unordered_map<std::string, std::string> output;
 
@@ -204,6 +209,7 @@ struct IpcMessage_IndexTranslationUnitResponse : public BaseIpcMessage<IpcMessag
   static constexpr IpcId kIpcId = IpcId::IndexTranslationUnitResponse;
   IndexUpdate update;
 
+  IpcMessage_IndexTranslationUnitResponse() {}
   explicit IpcMessage_IndexTranslationUnitResponse(IndexUpdate& update) : update(update) {}
 };
 template<typename TVisitor>
@@ -310,10 +316,10 @@ struct Timer {
 };
 
 
-void IndexMainLoop(IpcClient* ipc) {
-  std::vector<std::unique_ptr<IpcMessage>> messages = ipc->TakeMessages();
+void IndexMainLoop(IpcClient* client) {
+  std::vector<std::unique_ptr<IpcMessage>> messages = client->TakeMessages();
   for (auto& message : messages) {
-    std::cerr << "Processing message " << static_cast<int>(message->ipc_id) << std::endl;
+    //std::cerr << "Processing message " << static_cast<int>(message->ipc_id) << std::endl;
 
     switch (message->ipc_id) {
     case IpcId::Quit: {
@@ -335,7 +341,7 @@ void IndexMainLoop(IpcClient* ipc) {
       std::cerr << "Creating index update took " << time.ElapsedMilliseconds() << "ms" << std::endl;
 
       time.Reset();
-      ipc->SendToServer(&response);
+      client->SendToServer(&response);
       std::cerr << "Sending to server took " << time.ElapsedMilliseconds() << "ms" << std::endl;
 
       break;
@@ -345,10 +351,7 @@ void IndexMainLoop(IpcClient* ipc) {
 }
 
 void IndexMain(int id) {
-  return;
-
-  IpcClient client_ipc("indexer", id);
-
+  IpcClient client_ipc(kIpcIndexerName, id);
   while (true) {
     IndexMainLoop(&client_ipc);
     std::this_thread::sleep_for(std::chrono::milliseconds(10));
@@ -367,11 +370,41 @@ void IndexMain(int id) {
 
 
 
-void QueryDbMainLoop(IpcServer* client, std::vector<std::unique_ptr<IpcServer>>& indexers, QueryableDatabase* db) {
-  std::vector<std::unique_ptr<IpcMessage>> messages = client->TakeMessages();
 
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+void QueryDbMainLoop(IpcServer* language_client, IpcServer* indexers, QueryableDatabase* db) {
+  std::vector<std::unique_ptr<IpcMessage>> messages = language_client->TakeMessages();
   for (auto& message : messages) {
-    std::cerr << "Processing message " << static_cast<int>(message->ipc_id) << std::endl;
+    //std::cerr << "Processing message " << static_cast<int>(message->ipc_id) << std::endl;
 
     switch (message->ipc_id) {
     case IpcId::Quit: {
@@ -380,7 +413,7 @@ void QueryDbMainLoop(IpcServer* client, std::vector<std::unique_ptr<IpcServer>>&
 
     case IpcId::IsAlive: {
       IpcMessage_IsAlive response;
-      client->SendToClient(&response); // todo: make non-blocking
+      language_client->SendToClient(0, &response); // todo: make non-blocking
       break;
     }
 
@@ -395,11 +428,11 @@ void QueryDbMainLoop(IpcServer* client, std::vector<std::unique_ptr<IpcServer>>&
         std::string filepath = path + "/" + entry.filename;
         std::cerr << "[" << i << "/" << (entries.size() - 1) << "] Dispatching index request for file " << filepath << std::endl;
 
-        // TODO: indexers should steal work. load balance.
+        // TODO: indexers should steal work and load balance.
         IpcMessage_IndexTranslationUnitRequest request;
         request.path = filepath;
         request.args = entry.args;
-        indexers[i % indexers.size()]->SendToClient(&request);
+        indexers->SendToClient(i % indexers->num_clients(), &request);
         //IndexedFile file = Parse(filepath, entry.args);
         //IndexUpdate update(file);
         //db->ApplyIndexUpdate(&update);
@@ -408,14 +441,6 @@ void QueryDbMainLoop(IpcServer* client, std::vector<std::unique_ptr<IpcServer>>&
       break;
     }
 
-    case IpcId::IndexTranslationUnitResponse: {
-      IpcMessage_IndexTranslationUnitResponse* msg = static_cast<IpcMessage_IndexTranslationUnitResponse*>(message.get());
-      Timer time;
-      db->ApplyIndexUpdate(&msg->update);
-      std::cerr << "Applying index update took " << time.ElapsedMilliseconds() << "ms" << std::endl;
-      break;
-    }
-
     case IpcId::DocumentSymbolsRequest: {
       auto msg = static_cast<IpcMessage_DocumentSymbolsRequest*>(message.get());
 
@@ -487,7 +512,7 @@ void QueryDbMainLoop(IpcServer* client, std::vector<std::unique_ptr<IpcServer>>&
 
 
 
-      client->SendToClient(&response);
+      language_client->SendToClient(0, &response);
 
       break;
     }
@@ -577,7 +602,27 @@ void QueryDbMainLoop(IpcServer* client, std::vector<std::unique_ptr<IpcServer>>&
       }
 
 
-      client->SendToClient(&response);
+      language_client->SendToClient(0, &response);
+      break;
+    }
+
+    default: {
+      std::cerr << "Unhandled IPC message with kind " << static_cast<int>(message->ipc_id) << std::endl;
+      exit(1);
+    }
+    }
+  }
+
+  messages = indexers->TakeMessages();
+  for (auto& message : messages) {
+    //std::cerr << "Processing message " << static_cast<int>(message->ipc_id) << std::endl;
+    switch (message->ipc_id) {
+
+    case IpcId::IndexTranslationUnitResponse: {
+      IpcMessage_IndexTranslationUnitResponse* msg = static_cast<IpcMessage_IndexTranslationUnitResponse*>(message.get());
+      Timer time;
+      db->ApplyIndexUpdate(&msg->update);
+      std::cerr << "Applying index update took " << time.ElapsedMilliseconds() << "ms" << std::endl;
       break;
     }
 
@@ -588,6 +633,54 @@ void QueryDbMainLoop(IpcServer* client, std::vector<std::unique_ptr<IpcServer>>&
     }
   }
 }
+
+void QueryDbMain() {
+  std::cerr << "Running QueryDb" << std::endl;
+  IpcServer language_client(kIpcLanguageClientName, 1 /*num_clients*/);
+  IpcServer indexers(kIpcIndexerName, kNumIndexers);
+  QueryableDatabase db;
+
+  std::cerr << "!! starting processes" << std::endl;
+  // Start indexer processes.
+  for (int i = 0; i < kNumIndexers; ++i) {
+    //new Process(process_name + " --indexer " + std::to_string(i + 1));
+    new std::thread([i]() {
+      IndexMain(i);
+    });
+  }
+  std::cerr << "!! done processes" << std::endl;
+
+  // Pump query db main loop.
+  while (true) {
+    QueryDbMainLoop(&language_client, &indexers, &db);
+    std::this_thread::sleep_for(std::chrono::milliseconds(10));
+  }
+}
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@@ -722,10 +815,8 @@ void LanguageServerMainLoop(IpcClient* ipc) {
   }
 }
 
-const int kNumIndexers = 8 - 1;
-
 void LanguageServerMain(std::string process_name) {
-  IpcClient client_ipc("languageserver", 0);
+  IpcClient client_ipc(kIpcLanguageClientName, 0);
 
   // Discard any left-over messages from previous runs.
   client_ipc.TakeMessages();
@@ -767,55 +858,30 @@ void LanguageServerMain(std::string process_name) {
     // Pass empty process name so we only try to start the querydb once.
     LanguageServerMain("");
     return;
-  }
+}
 #endif
 
   // for debugging attach
   //std::this_thread::sleep_for(std::chrono::seconds(4));
 
 
-  std::thread stdio_reader(&LanguageServerStdinLoop, &client_ipc);
 
 
 
   if (!has_server) {
-    std::vector<std::unique_ptr<IpcServer>> server_indexers;
-    IpcServer server_ipc("languageserver", 0);
-    QueryableDatabase db;
-
     // No server. Run it in-process.
     new std::thread([&]() {
-
-      std::cerr << "!! starting processes" << std::endl;
-      // Start indexer processes.
-      // TODO: make sure to handle this when running querydb out of process.
-      for (int i = 0; i < kNumIndexers; ++i) {
-        server_indexers.emplace_back(MakeUnique<IpcServer>("indexer", i + 1));
-        //new Process(process_name + " --indexer " + std::to_string(i + 1));
-        new std::thread([i]() {
-          IndexMain(i + 1);
-        });
-      }
-      std::cerr << "!! done processes" << std::endl;
-
-
-      
-      while (true) {
-        QueryDbMainLoop(&server_ipc, server_indexers, &db);
-        std::this_thread::sleep_for(std::chrono::milliseconds(10));
-      }
+      QueryDbMain();
     });
   }
 
   // Run language client.
+  std::thread stdio_reader(&LanguageServerStdinLoop, &client_ipc);
   while (true) {
     LanguageServerMainLoop(&client_ipc);
     std::this_thread::sleep_for(std::chrono::milliseconds(10));
   }
-}
-
-
-
+  }
 
 
 
@@ -860,16 +926,9 @@ void LanguageServerMain(std::string process_name) {
 
 
 
-int main(int argc, char** argv) {
-  bool loop = false;
-  while (loop)
-    std::this_thread::sleep_for(std::chrono::milliseconds(10));
 
-  if (argc == 1) {
-    RunTests();
-    return 0;
-  }
 
+void PreMain() {
   // We need to write to stdout in binary mode because in Windows, writing
   // \n will implicitly write \r\n. Language server API will ignore a
   // \r\r\n split request.
@@ -878,21 +937,40 @@ int main(int argc, char** argv) {
   _setmode(_fileno(stdin), O_BINARY);
 #endif
 
-  IpcRegistry::instance()->Register<IpcMessage_Quit>(IpcId::Quit);
-  IpcRegistry::instance()->Register<IpcMessage_IsAlive>(IpcId::IsAlive);
-  IpcRegistry::instance()->Register<IpcMessage_OpenProject>(IpcId::OpenProject);
+  IpcRegistry::instance()->Register<IpcMessage_Quit>(IpcMessage_Quit::kIpcId);
+  IpcRegistry::instance()->Register<IpcMessage_IsAlive>(IpcMessage_IsAlive::kIpcId);
+  IpcRegistry::instance()->Register<IpcMessage_OpenProject>(IpcMessage_OpenProject::kIpcId);
+
+  IpcRegistry::instance()->Register<IpcMessage_IndexTranslationUnitRequest>(IpcMessage_IndexTranslationUnitRequest::kIpcId);
+  IpcRegistry::instance()->Register<IpcMessage_IndexTranslationUnitResponse>(IpcMessage_IndexTranslationUnitResponse::kIpcId);
 
-  IpcRegistry::instance()->Register<IpcMessage_DocumentSymbolsRequest>(IpcId::DocumentSymbolsRequest);
-  IpcRegistry::instance()->Register<IpcMessage_DocumentSymbolsResponse>(IpcId::DocumentSymbolsResponse);
-  IpcRegistry::instance()->Register<IpcMessage_WorkspaceSymbolsRequest>(IpcId::WorkspaceSymbolsRequest);
-  IpcRegistry::instance()->Register<IpcMessage_WorkspaceSymbolsResponse>(IpcId::WorkspaceSymbolsResponse);
+  IpcRegistry::instance()->Register<IpcMessage_DocumentSymbolsRequest>(IpcMessage_DocumentSymbolsRequest::kIpcId);
+  IpcRegistry::instance()->Register<IpcMessage_DocumentSymbolsResponse>(IpcMessage_DocumentSymbolsResponse::kIpcId);
+  IpcRegistry::instance()->Register<IpcMessage_WorkspaceSymbolsRequest>(IpcMessage_WorkspaceSymbolsRequest::kIpcId);
+  IpcRegistry::instance()->Register<IpcMessage_WorkspaceSymbolsResponse>(IpcMessage_WorkspaceSymbolsResponse::kIpcId);
 
   MessageRegistry::instance()->Register<In_CancelRequest>();
   MessageRegistry::instance()->Register<In_InitializeRequest>();
   MessageRegistry::instance()->Register<In_InitializedNotification>();
   MessageRegistry::instance()->Register<In_DocumentSymbolRequest>();
   MessageRegistry::instance()->Register<In_WorkspaceSymbolRequest>();
+}
+
+int main(int argc, char** argv) {
+  bool loop = false;
+  while (loop)
+    std::this_thread::sleep_for(std::chrono::milliseconds(10));
 
+  PreMain();
+
+  if (argc == 1) {
+    QueryDbMain();
+    return 0;
+  }
+  if (argc == 1) {
+    RunTests();
+    return 0;
+  }
 
 
 
@@ -909,7 +987,7 @@ int main(int argc, char** argv) {
   else if (HasOption(options, "--querydb")) {
     std::cerr << "Running querydb" << std::endl;
     QueryableDatabase db;
-    IpcServer ipc("languageserver");
+    IpcServer ipc(kIpcServername);
     while (true) {
       QueryDbMainLoop(&ipc, &db);
       // TODO: use a condition variable.

full_tests/simple_cross_reference/c.cc

@@ -0,0 +1,9 @@
+#include "a.h"
+
+#if RANDOM_DEFINE
+static void LocalC() {
+  Common();
+}
+#endif  // RANDOM_DEFINE
+
+static void LocalD() {}

ipc.cc

@@ -45,14 +45,18 @@ namespace {
 IpcRegistry* IpcRegistry::instance_ = nullptr;
 
 std::unique_ptr<IpcMessage> IpcRegistry::Allocate(IpcId id) {
-  return std::unique_ptr<IpcMessage>((*allocators)[id]());
+  assert(allocators_);
+  auto it = allocators_->find(id);
+  assert(it != allocators_->end() && "No registered allocator for id");
+  return std::unique_ptr<IpcMessage>(it->second());
 }
 
 struct IpcDirectionalChannel::MessageBuffer {
-  MessageBuffer(void* buffer, size_t buffer_size) {
+  MessageBuffer(void* buffer, size_t buffer_size, bool initialize) {
     real_buffer = buffer;
     real_buffer_size = buffer_size;
-    new(real_buffer) Metadata();
+    if (initialize)
+      new(real_buffer) Metadata();
   }
 
   // Pointer to the start of the actual buffer and the
@@ -201,15 +205,15 @@ void IpcDirectionalChannel::RemoveResizableBuffer(int id) {
   resizable_buffers.erase(id);
 }
 
-IpcDirectionalChannel::IpcDirectionalChannel(const std::string& name) {
+IpcDirectionalChannel::IpcDirectionalChannel(const std::string& name, bool initialize_shared_memory) {
   shared = CreatePlatformSharedMemory(name + "memory");
   mutex = CreatePlatformMutex(name + "mutex");
   local = std::unique_ptr<char>(new char[shmem_size]);
 
   // TODO: connecting a client will allocate reset shared state on the
   // buffer. We need to store if we "initialized".
-  shared_buffer = MakeUnique<MessageBuffer>(shared->shared, shmem_size);
-  local_buffer = MakeUnique<MessageBuffer>(local.get(), shmem_size);
+  shared_buffer = MakeUnique<MessageBuffer>(shared->shared, shmem_size, initialize_shared_memory);
+  local_buffer = MakeUnique<MessageBuffer>(local.get(), shmem_size, true /*initialize*/);
 }
 
 IpcDirectionalChannel::~IpcDirectionalChannel() {}
@@ -361,11 +365,16 @@ std::vector<std::unique_ptr<IpcMessage>> IpcDirectionalChannel::TakeMessages() {
 
 
 
-IpcServer::IpcServer(const std::string& name, int client_id)
-  : server_(NameToServerName(name)), client_(NameToClientName(name, client_id)) {}
+IpcServer::IpcServer(const std::string& name, int num_clients)
+  : server_(NameToServerName(name), true /*initialize_shared_memory*/) {
 
-void IpcServer::SendToClient(IpcMessage* message) {
-  client_.PushMessage(message);
+  for (int i = 0; i < num_clients; ++i) {
+    clients_.push_back(MakeUnique<IpcDirectionalChannel>(NameToClientName(name, i), true /*initialize_shared_memory*/));
+  }
+}
+
+void IpcServer::SendToClient(int client_id, IpcMessage* message) {
+  clients_[client_id]->PushMessage(message);
 }
 
 std::vector<std::unique_ptr<IpcMessage>> IpcServer::TakeMessages() {
@@ -373,7 +382,8 @@ std::vector<std::unique_ptr<IpcMessage>> IpcServer::TakeMessages() {
 }
 
 IpcClient::IpcClient(const std::string& name, int client_id)
-  : server_(NameToServerName(name)), client_(NameToClientName(name, client_id)) {}
+  : server_(NameToServerName(name), false /*initialize_shared_memory*/),
+    client_(NameToClientName(name, client_id), false /*initialize_shared_memory*/) {}
 
 void IpcClient::SendToServer(IpcMessage* message) {
   server_.PushMessage(message);

ipc.h

@@ -61,7 +61,7 @@ struct IpcRegistry {
 
   // Use unique_ptrs so we can initialize on first use
   // (static init order might not be right).
-  std::unique_ptr<std::unordered_map<IpcId, Allocator>> allocators;
+  std::unique_ptr<std::unordered_map<IpcId, Allocator>> allocators_;
 
   template<typename T>
   void Register(IpcId id);
@@ -78,13 +78,13 @@ struct IpcRegistry {
 
 template<typename T>
 void IpcRegistry::Register(IpcId id) {
-  if (!allocators)
-    allocators = MakeUnique<std::unordered_map<IpcId, Allocator>>();
+  if (!allocators_)
+    allocators_ = MakeUnique<std::unordered_map<IpcId, Allocator>>();
 
-  assert(allocators->find(id) == allocators->end() &&
+  assert(allocators_->find(id) == allocators_->end() &&
          "There is already an IPC message with the given id");
 
-  (*allocators)[id] = [id]() {
+  (*allocators_)[id] = [id]() {
     return new T();
   };
 }
@@ -98,7 +98,7 @@ struct IpcDirectionalChannel {
   // NOTE: We keep all pointers in terms of char* so pointer arithmetic is
   // always relative to bytes.
 
-  explicit IpcDirectionalChannel(const std::string& name);
+  explicit IpcDirectionalChannel(const std::string& name, bool initialize_shared_memory);
   ~IpcDirectionalChannel();
 
   void PushMessage(IpcMessage* message);
@@ -123,14 +123,16 @@ struct IpcDirectionalChannel {
 };
 
 struct IpcServer {
-  IpcServer(const std::string& name, int client_id);
+  IpcServer(const std::string& name, int num_clients);
 
-  void SendToClient(IpcMessage* message);
+  void SendToClient(int client_id, IpcMessage* message);
   std::vector<std::unique_ptr<IpcMessage>> TakeMessages();
 
+  int num_clients() const { return clients_.size(); }
+
 private:
-  IpcDirectionalChannel server_;
-  IpcDirectionalChannel client_;
+  IpcDirectionalChannel server_; // Local / us.
+  std::vector<std::unique_ptr<IpcDirectionalChannel>> clients_;
 };
 
 struct IpcClient {

platform.h

@@ -12,6 +12,7 @@ struct PlatformScopedMutexLock {
 struct PlatformSharedMemory {
   virtual ~PlatformSharedMemory() {}
   void* shared;
+  std::string name;
 };
 
 const int shmem_size = 1024 * 1024 * 32;  // number of chars/bytes (32mb)

platform_win.cc

@@ -37,6 +37,8 @@ struct PlatformSharedMemoryWin : public PlatformSharedMemory {
   HANDLE shmem_;
 
   PlatformSharedMemoryWin(const std::string& name) {
+    this->name = name;
+
     shmem_ = CreateFileMapping(
       INVALID_HANDLE_VALUE,
       NULL,

query.cc

@@ -512,37 +512,77 @@ void QueryableDatabase::RemoveUsrs(const std::vector<Usr>& to_remove) {
 
 void QueryableDatabase::Import(const std::vector<QueryableFile>& defs) {
   for (auto& def : defs) {
-    qualified_names.push_back(def.file_id);
-    symbols.push_back(SymbolIdx(SymbolKind::File, files.size()));
-    usr_to_symbol[def.file_id] = SymbolIdx(SymbolKind::File, files.size());
-    files.push_back(def);
+    auto it = usr_to_symbol.find(def.file_id);
+    if (it == usr_to_symbol.end()) {
+      qualified_names.push_back(def.file_id);
+      symbols.push_back(SymbolIdx(SymbolKind::File, files.size()));
+      usr_to_symbol[def.file_id] = SymbolIdx(SymbolKind::File, files.size());
+
+      files.push_back(def);
+    }
+    else {
+      QueryableFile& existing = files[it->second.idx];
+      // Replace the entire file. We don't ever want to merge files.
+      existing = def;
+    }
   }
 }
 
 void QueryableDatabase::Import(const std::vector<QueryableTypeDef>& defs) {
   for (auto& def : defs) {
-    qualified_names.push_back(def.def.qualified_name);
-    symbols.push_back(SymbolIdx(SymbolKind::Type, types.size()));
-    usr_to_symbol[def.def.usr] = SymbolIdx(SymbolKind::Type, types.size());
-    types.push_back(def);
+    auto it = usr_to_symbol.find(def.def.usr);
+    if (it == usr_to_symbol.end()) {
+      qualified_names.push_back(def.def.qualified_name);
+      symbols.push_back(SymbolIdx(SymbolKind::Type, types.size()));
+      usr_to_symbol[def.def.usr] = SymbolIdx(SymbolKind::Type, types.size());
+      types.push_back(def);
+    }
+    else {
+      QueryableTypeDef& existing = types[it->second.idx];
+      if (def.def.definition)
+        existing.def = def.def;
+      AddRange(&existing.derived, def.derived);
+      AddRange(&existing.uses, def.uses);
+    }
   }
 }
 
 void QueryableDatabase::Import(const std::vector<QueryableFuncDef>& defs) {
   for (auto& def : defs) {
-    qualified_names.push_back(def.def.qualified_name);
-    symbols.push_back(SymbolIdx(SymbolKind::Func, funcs.size()));
-    usr_to_symbol[def.def.usr] = SymbolIdx(SymbolKind::Func, funcs.size());
-    funcs.push_back(def);
+    auto it = usr_to_symbol.find(def.def.usr);
+    if (it == usr_to_symbol.end()) {
+      qualified_names.push_back(def.def.qualified_name);
+      symbols.push_back(SymbolIdx(SymbolKind::Func, funcs.size()));
+      usr_to_symbol[def.def.usr] = SymbolIdx(SymbolKind::Func, funcs.size());
+      funcs.push_back(def);
+    }
+    else {
+      QueryableFuncDef& existing = funcs[it->second.idx];
+      if (def.def.definition)
+        existing.def = def.def;
+      AddRange(&existing.callers, def.callers);
+      AddRange(&existing.declarations, def.declarations);
+      AddRange(&existing.derived, def.derived);
+      AddRange(&existing.uses, def.uses);
+    }
   }
 }
 
 void QueryableDatabase::Import(const std::vector<QueryableVarDef>& defs) {
   for (auto& def : defs) {
-    qualified_names.push_back(def.def.qualified_name);
-    symbols.push_back(SymbolIdx(SymbolKind::Var, vars.size()));
-    usr_to_symbol[def.def.usr] = SymbolIdx(SymbolKind::Var, vars.size());
-    vars.push_back(def);
+    auto it = usr_to_symbol.find(def.def.usr);
+    if (it == usr_to_symbol.end()) {
+      qualified_names.push_back(def.def.qualified_name);
+      symbols.push_back(SymbolIdx(SymbolKind::Var, vars.size()));
+      usr_to_symbol[def.def.usr] = SymbolIdx(SymbolKind::Var, vars.size());
+      vars.push_back(def);
+    }
+    else {
+      QueryableVarDef& existing = vars[it->second.idx];
+      if (def.def.definition)
+        existing.def = def.def;
+      AddRange(&existing.uses, def.uses);
+    }
   }
 }
 

query.h

@@ -271,6 +271,7 @@ struct IndexUpdate {
   std::vector<QueryableVarDef::DefUpdate> vars_def_changed;
   std::vector<QueryableVarDef::UsesUpdate> vars_uses;
 
+  IndexUpdate() {}
 
   // Creates a new IndexUpdate that will import |file|.
   explicit IndexUpdate(IndexedFile& file);