From 6710dbc2e9dc4b3bff1438e5be9549d147507b5d Mon Sep 17 00:00:00 2001
From: Fangrui Song <i@maskray.me>
Date: Thu, 11 Apr 2019 22:26:07 -0700
Subject: [PATCH] Set RetainCommentsFromSystemHeaders to true

Note with -fretain-comments-from-system-headers, the .gch of bits/stdc++.h becomes larger by 1%, but that is fine.

Fix #373
---
 src/indexer.cc      | 4 ++--
 src/sema_manager.cc | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/indexer.cc b/src/indexer.cc
index 59135710..066fc9f1 100644
--- a/src/indexer.cc
+++ b/src/indexer.cc
@@ -1238,8 +1238,8 @@ Index(SemaManager *manager, WorkingFiles *wfiles, VFS *vfs,
   ok = false;
   // -fparse-all-comments enables documentation in the indexer and in
   // code completion.
-  if (g_config->index.comments > 1)
-    CI->getLangOpts()->CommentOpts.ParseAllComments = true;
+  CI->getLangOpts()->CommentOpts.ParseAllComments = g_config->index.comments > 1;
+  CI->getLangOpts()->RetainCommentsFromSystemHeaders = true;
   std::string buf = wfiles->GetContent(main);
   std::vector<std::unique_ptr<llvm::MemoryBuffer>> Bufs;
   if (buf.size())
diff --git a/src/sema_manager.cc b/src/sema_manager.cc
index 096f2c16..d8e7608e 100644
--- a/src/sema_manager.cc
+++ b/src/sema_manager.cc
@@ -363,6 +363,7 @@ void BuildPreamble(Session &session, CompilerInvocation &CI,
   CI.getDiagnosticOpts().IgnoreWarnings = false;
   CI.getFrontendOpts().SkipFunctionBodies = true;
   CI.getLangOpts()->CommentOpts.ParseAllComments = g_config->index.comments > 1;
+  CI.getLangOpts()->RetainCommentsFromSystemHeaders = true;
 
   StoreDiags DC(task.path);
   IntrusiveRefCntPtr<DiagnosticsEngine> DE =