Completion changes (maybe fix some crashes)

src/clang_complete.cc

@@ -8,7 +8,41 @@
 #include <algorithm>
 #include <thread>
 
+/*
+#include <execinfo.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+*/
+
+
 namespace {
+
+constexpr int kBacktraceBufferSize = 300;
+
+#if false
+void EmitBacktrace() {
+   void* buffer[kBacktraceBufferSize];
+   int nptrs = backtrace(buffer, kBacktraceBufferSize);
+
+   fprintf(stderr, "backtrace() returned %d addresses\n", nptrs);
+
+   /* The call backtrace_symbols_fd(buffer, nptrs, STDOUT_FILENO)
+      would produce similar output to the following: */
+
+   char** strings = backtrace_symbols(buffer, nptrs);
+   if (!strings) {
+       perror("Failed to emit backtrace");
+       exit(EXIT_FAILURE);
+   }
+
+   for (int j = 0; j < nptrs; j++)
+       fprintf(stderr, "%s\n", strings[j]);
+
+   free(strings);
+}
+#endif
+
 unsigned Flags() {
   // TODO: use clang_defaultEditingTranslationUnitOptions()?
   return
@@ -333,6 +367,7 @@ void CompletionQueryMain(ClangCompleteManager* completion_manager) {
     timer.ResetAndPrint("[complete] clangCodeCompleteAt");
     std::cerr << "[complete] Got " << cx_results->NumResults << " results" << std::endl;
 
+    {
       NonElidedVector<lsCompletionItem> ls_result;
       ls_result.reserve(cx_results->NumResults);
 
@@ -368,11 +403,14 @@ void CompletionQueryMain(ClangCompleteManager* completion_manager) {
       }
       timer.ResetAndPrint("[complete] Building " + std::to_string(ls_result.size()) + " completion results");
 
+      request->on_complete(ls_result);
+      timer.ResetAndPrint("[complete] Running user-given completion func");
+    }
+
+    // Make sure |ls_results| is destroyed before clearing |cx_results|.
     clang_disposeCodeCompleteResults(cx_results);
     timer.ResetAndPrint("[complete] clang_disposeCodeCompleteResults");
 
-    request->on_complete(ls_result);
-
     continue;
   }
 }
@@ -386,6 +424,7 @@ CompletionSession::CompletionSession(const Project::Entry& file, WorkingFiles* w
 
 CompletionSession::~CompletionSession() {
   std::cerr << "[complete] CompletionSession::~CompletionSession() for " << file.filename << std::endl;
+  // EmitBacktrace();
 }
 
 LruSessionCache::LruSessionCache(int max_entries) : max_entries_(max_entries) {}
@@ -401,7 +440,7 @@ std::shared_ptr<CompletionSession> LruSessionCache::TryGetEntry(const std::strin
 std::shared_ptr<CompletionSession> LruSessionCache::TryTakeEntry(const std::string& filename) {
   for (int i = 0; i < entries_.size(); ++i) {
     if (entries_[i]->file.filename == filename) {
-      std::shared_ptr<CompletionSession> result = std::move(entries_[i]);
+      std::shared_ptr<CompletionSession> result = entries_[i];
       entries_.erase(entries_.begin() + i);
       return result;
     }
@@ -410,9 +449,9 @@ std::shared_ptr<CompletionSession> LruSessionCache::TryTakeEntry(const std::stri
 }
 
 void LruSessionCache::InsertEntry(std::shared_ptr<CompletionSession> session) {
-  if (entries_.size() >= max_entries_)
+  if (entries_.size() && entries_.size() >= max_entries_)
     entries_.pop_back();
-  entries_.insert(entries_.begin(), std::move(session));
+  entries_.insert(entries_.begin(), session);
 }
 
 ClangCompleteManager::ParseRequest::ParseRequest(const std::string& path)
@@ -432,6 +471,8 @@ ClangCompleteManager::ClangCompleteManager(Config* config, Project* project, Wor
   });
 }
 
+ClangCompleteManager::~ClangCompleteManager() {}
+
 void ClangCompleteManager::CodeComplete(const lsTextDocumentPositionParams& completion_location, const OnComplete& on_complete) {
   // completion thread will create the CompletionSession if needed.
 
@@ -454,7 +495,7 @@ void ClangCompleteManager::NotifyView(const std::string& filename) {
     return;
 
   std::cerr << "[complete] Creating new edit code completion session for " << filename << std::endl;
-  view_sessions_.InsertEntry(MakeUnique<CompletionSession>(
+  view_sessions_.InsertEntry(std::make_shared<CompletionSession>(
     project_->FindCompilationEntryForFile(filename), working_files_));
   parse_requests_.Enqueue(ParseRequest(filename));
 }
@@ -471,14 +512,16 @@ void ClangCompleteManager::NotifyEdit(const std::string& filename) {
   if (edit_sessions_.TryGetEntry(filename))
     return;
 
-  if (std::shared_ptr<CompletionSession> session = view_sessions_.TryTakeEntry(filename)) {
+  std::shared_ptr<CompletionSession> session = view_sessions_.TryTakeEntry(filename);
-    edit_sessions_.InsertEntry(std::move(session));
+  if (session) {
+    edit_sessions_.InsertEntry(session);
   }
-
+  else {
     std::cerr << "[complete] Creating new edit code completion session for " << filename << std::endl;
-  edit_sessions_.InsertEntry(MakeUnique<CompletionSession>(
+    edit_sessions_.InsertEntry(std::make_shared<CompletionSession>(
       project_->FindCompilationEntryForFile(filename), working_files_));
     parse_requests_.PriorityEnqueue(ParseRequest(filename));
+  }
 }
 
 void ClangCompleteManager::NotifySave(const std::string& filename) {
@@ -490,7 +533,7 @@ void ClangCompleteManager::NotifySave(const std::string& filename) {
 
   if (!edit_sessions_.TryGetEntry(filename)) {
     std::cerr << "[complete] Creating new edit code completion session for " << filename << std::endl;
-    edit_sessions_.InsertEntry(MakeUnique<CompletionSession>(
+    edit_sessions_.InsertEntry(std::make_shared<CompletionSession>(
       project_->FindCompilationEntryForFile(filename), working_files_));
   }
 
@@ -508,7 +551,7 @@ std::shared_ptr<CompletionSession> ClangCompleteManager::TryGetSession(const std
   if (!session && create_if_needed) {
     // Create new session. Default to edited_sessions_ since invoking code
     // completion almost certainly implies an edit.
-    edit_sessions_.InsertEntry(MakeUnique<CompletionSession>(
+    edit_sessions_.InsertEntry(std::make_shared<CompletionSession>(
       project_->FindCompilationEntryForFile(filename), working_files_));
     session = edit_sessions_.TryGetEntry(filename);
   }

src/clang_complete.h

@@ -62,6 +62,7 @@ struct ClangCompleteManager {
   };
 
   ClangCompleteManager(Config* config, Project* project, WorkingFiles* working_files, OnDiagnostic on_diagnostic);
+  ~ClangCompleteManager();
 
   // Start a code completion at the given location. |on_complete| will run when
   // completion results are available. |on_complete| may run on any thread.

src/command_line.cc

@@ -1672,10 +1672,13 @@ bool QueryDbMainLoop(
               // note: path is updated in the normal completion handler.
               global_code_complete_cache->cached_results = results;
             };
-            clang_complete->CodeComplete(msg->params, std::move(freshen_global));
 
-            // Note: callback will delete the message (ie, |params|) so we need to run completion_manager->CodeComplete before |callback|.
+            // Note: |callback| will delete the message (ie, |params|) so we
+            // need to run completion_manager->CodeComplete before |callback|.
+            lsTextDocumentPositionParams params = msg->params;
             callback(global_code_complete_cache->cached_results);
+
+            clang_complete->CodeComplete(params, std::move(freshen_global));
           }
           else if (non_global_code_complete_cache->IsCacheValid(msg->params)) {
             std::cerr << "[complete] Using cached completion results at " << msg->params.position.ToString() << std::endl;