From 008b1762c1bc3c6fe57c71a092633e24887e17c7 Mon Sep 17 00:00:00 2001
From: Fangrui Song <i@maskray.me>
Date: Thu, 22 Nov 2018 20:07:39 -0800
Subject: [PATCH] indexer: handle DecltypeType and empty main file; diag:
 -Wno-unused-function for headers

Don't replace name with qualified name in Cls::*name
---
 src/clang_complete.cc |  3 +++
 src/indexer.cc        | 31 ++++++++++++++++++++++++-------
 2 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/src/clang_complete.cc b/src/clang_complete.cc
index b3466ad4..3e52839f 100644
--- a/src/clang_complete.cc
+++ b/src/clang_complete.cc
@@ -470,6 +470,9 @@ void *DiagnosticMain(void *manager_) {
         BuildCompilerInvocation(session->file.args, FS);
     if (!CI)
       continue;
+    // If main file is a header, add -Wno-unused-function
+    if (lookupExtension(session->file.filename).second)
+      CI->getDiagnosticOpts().Warnings.push_back("no-unused-function");
     CI->getDiagnosticOpts().IgnoreWarnings = false;
     CI->getLangOpts()->SpellChecking = g_config->diagnostics.spellChecking;
     StoreDiags DC(path);
diff --git a/src/indexer.cc b/src/indexer.cc
index 3a7aecf3..bc10732f 100644
--- a/src/indexer.cc
+++ b/src/indexer.cc
@@ -513,11 +513,12 @@ public:
       // e.g. operator type-parameter-1
       i = 0;
       def.short_name_offset = 0;
-    } else if (short_name.size() && (!i || name[i - 1] != ':')) {
+    } else if (short_name.empty() || (i >= 2 && name[i - 2] == ':')) {
+      // Don't replace name with qualified name in ns::name Cls::*name
+      def.short_name_offset = i;
+    } else {
       name.replace(i, short_name.size(), qualified);
       def.short_name_offset = i + qualified.size() - short_name.size();
-    } else {
-      def.short_name_offset = i;
     }
     def.short_name_size = short_name.size();
     for (int paren = 0; i; i--) {
@@ -538,7 +539,7 @@ public:
                   std::string_view qualified, IndexVar::Def &def) {
     QualType T;
     const Expr *init = nullptr;
-    bool binding = false;
+    bool deduced = false;
     if (auto *VD = dyn_cast<VarDecl>(D)) {
       T = VD->getType();
       init = VD->getAnyInitializer();
@@ -548,9 +549,21 @@ public:
       init = FD->getInClassInitializer();
     } else if (auto *BD = dyn_cast<BindingDecl>(D)) {
       T = BD->getType();
-      binding = true;
+      deduced = true;
     }
-    if (!T.isNull() && (binding || T->getContainedDeducedType())) {
+    if (!T.isNull()) {
+      if (T->getContainedDeducedType()) {
+        deduced = true;
+      } else if (auto *DT = dyn_cast<DecltypeType>(T)) {
+        // decltype(y) x;
+        while (DT && !DT->getUnderlyingType().isNull()) {
+          T = DT->getUnderlyingType();
+          DT = dyn_cast<DecltypeType>(T);
+        }
+        deduced = true;
+      }
+    }
+    if (!T.isNull() && deduced) {
       SmallString<256> Str;
       llvm::raw_svector_ostream OS(Str);
       PrintingPolicy PP = GetDefaultPolicy();
@@ -657,7 +670,11 @@ public:
 
 public:
   IndexDataConsumer(IndexParam &param) : param(param) {}
-  void initialize(ASTContext &Ctx) override { this->Ctx = param.Ctx = &Ctx; }
+  void initialize(ASTContext &Ctx) override {
+    this->Ctx = param.Ctx = &Ctx;
+    SourceManager &SM = Ctx.getSourceManager();
+    (void)param.ConsumeFile(*SM.getFileEntryForID(SM.getMainFileID()));
+  }
   bool handleDeclOccurence(const Decl *D, index::SymbolRoleSet Roles,
                            ArrayRef<index::SymbolRelation> Relations,
 #if LLVM_VERSION_MAJOR >= 7