2 files changed, 79 insertions, 50 deletions

diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index 2acc896d53d..f7adaf4dcd0 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -3524,7 +3524,8 @@ void Sema::CodeCompleteOrdinaryName(Scope *S,
   
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
 
   AddOrdinaryNameResults(CompletionContext, S, *this, Results);
   Results.ExitScope();
@@ -3599,7 +3600,8 @@ void Sema::CodeCompleteDeclSpec(Scope *S, DeclSpec &DS,
       Results.setFilter(&ResultBuilder::IsImpossibleToSatisfy);
       CodeCompletionDeclConsumer Consumer(Results, CurContext);
       LookupVisibleDecls(S, LookupNestedNameSpecifierName, Consumer,
-                         CodeCompleter->includeGlobals());
+                         CodeCompleter->includeGlobals(),
+                         CodeCompleter->loadExternal());
       Results.setFilter(nullptr);
     }
   }
@@ -3669,8 +3671,9 @@ void Sema::CodeCompleteExpression(Scope *S,
   
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
-  
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
+
   Results.EnterNewScope();
   AddOrdinaryNameResults(PCC_Expression, S, *this, Results);
   Results.ExitScope();
@@ -3939,7 +3942,8 @@ static void AddRecordMembersCompletionResults(Sema &SemaRef,
   CodeCompletionDeclConsumer Consumer(Results, SemaRef.CurContext);
   SemaRef.LookupVisibleDecls(RD, Sema::LookupMemberName, Consumer,
                              SemaRef.CodeCompleter->includeGlobals(),
-                             /*IncludeDependentBases=*/true);
+                             /*IncludeDependentBases=*/true,
+                             SemaRef.CodeCompleter->loadExternal());
 
   if (SemaRef.getLangOpts().CPlusPlus) {
     if (!Results.empty()) {
@@ -4049,8 +4053,9 @@ void Sema::CodeCompleteMemberReferenceExpr(Scope *S, Expr *Base,
     if (Class) {
       CodeCompletionDeclConsumer Consumer(Results, CurContext);
       Results.setFilter(&ResultBuilder::IsObjCIvar);
-      LookupVisibleDecls(Class, LookupMemberName, Consumer,
-                         CodeCompleter->includeGlobals());
+      LookupVisibleDecls(
+          Class, LookupMemberName, Consumer, CodeCompleter->includeGlobals(),
+          /*IncludeDependentBases=*/false, CodeCompleter->loadExternal());
     }
   }
   
@@ -4124,12 +4129,15 @@ void Sema::CodeCompleteTag(Scope *S, unsigned TagSpec) {
   // First pass: look for tags.
   Results.setFilter(Filter);
   LookupVisibleDecls(S, LookupTagName, Consumer,
-                     CodeCompleter->includeGlobals());
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
 
   if (CodeCompleter->includeGlobals()) {
     // Second pass: look for nested name specifiers.
     Results.setFilter(&ResultBuilder::IsNestedNameSpecifier);
-    LookupVisibleDecls(S, LookupNestedNameSpecifierName, Consumer);
+    LookupVisibleDecls(S, LookupNestedNameSpecifierName, Consumer,
+                       CodeCompleter->includeGlobals(),
+                       CodeCompleter->loadExternal());
   }
   
   HandleCodeCompleteResults(this, CodeCompleter, Results.getCompletionContext(),
@@ -4540,8 +4548,9 @@ void Sema::CodeCompleteAfterIf(Scope *S) {
   
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
-  
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
+
   AddOrdinaryNameResults(PCC_Statement, S, *this, Results);
   
   // "else" block
@@ -4649,7 +4658,8 @@ void Sema::CodeCompleteQualifiedId(Scope *S, CXXScopeSpec &SS,
     CodeCompletionDeclConsumer Consumer(Results, CurContext);
     LookupVisibleDecls(Ctx, LookupOrdinaryName, Consumer,
                        /*IncludeGlobalScope=*/true,
-                       /*IncludeDependentBases=*/true);
+                       /*IncludeDependentBases=*/true,
+                       CodeCompleter->loadExternal());
   }
 
   auto CC = Results.getCompletionContext();
@@ -4677,7 +4687,8 @@ void Sema::CodeCompleteUsing(Scope *S) {
   // nested-name-specifier.
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
   Results.ExitScope();
   
   HandleCodeCompleteResults(this, CodeCompleter, 
@@ -4698,7 +4709,8 @@ void Sema::CodeCompleteUsingDirective(Scope *S) {
   Results.EnterNewScope();
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
   Results.ExitScope();
   HandleCodeCompleteResults(this, CodeCompleter, 
                             CodeCompletionContext::CCC_Namespace,
@@ -4764,7 +4776,8 @@ void Sema::CodeCompleteNamespaceAliasDecl(Scope *S)  {
                         &ResultBuilder::IsNamespaceOrAlias);
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
   HandleCodeCompleteResults(this, CodeCompleter, 
                             Results.getCompletionContext(),
                             Results.data(),Results.size());
@@ -4791,8 +4804,9 @@ void Sema::CodeCompleteOperatorName(Scope *S) {
   Results.allowNestedNameSpecifiers();
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
-  
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
+
   // Add any type specifiers
   AddTypeSpecifierResults(getLangOpts(), Results);
   Results.ExitScope();
@@ -5620,8 +5634,9 @@ void Sema::CodeCompleteObjCPassingType(Scope *S, ObjCDeclSpec &DS,
   Results.setFilter(&ResultBuilder::IsOrdinaryNonValueName);
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
-  
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
+
   if (CodeCompleter->includeMacros())
     AddMacroResults(PP, Results, false);
 
@@ -5834,8 +5849,9 @@ void Sema::CodeCompleteObjCMessageReceiver(Scope *S) {
   CodeCompletionDeclConsumer Consumer(Results, CurContext);
   Results.EnterNewScope();
   LookupVisibleDecls(S, LookupOrdinaryName, Consumer,
-                     CodeCompleter->includeGlobals());
-  
+                     CodeCompleter->includeGlobals(),
+                     CodeCompleter->loadExternal());
+
   // If we are in an Objective-C method inside a class that has a superclass,
   // add "super" as an option.
   if (ObjCMethodDecl *Method = getCurMethodDecl())
@@ -7942,8 +7958,9 @@ void Sema::GatherGlobalCodeCompletions(CodeCompletionAllocator &Allocator,
   if (!CodeCompleter || CodeCompleter->includeGlobals()) {
     CodeCompletionDeclConsumer Consumer(Builder, 
                                         Context.getTranslationUnitDecl());
-    LookupVisibleDecls(Context.getTranslationUnitDecl(), LookupAnyName, 
-                       Consumer);
+    LookupVisibleDecls(Context.getTranslationUnitDecl(), LookupAnyName,
+                       Consumer,
+                       !CodeCompleter || CodeCompleter->loadExternal());
   }
   
   if (!CodeCompleter || CodeCompleter->includeMacros())
diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index fb83c0f05e6..c44a375d731 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -3498,7 +3498,8 @@ static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
                                bool InBaseClass,
                                VisibleDeclConsumer &Consumer,
                                VisibleDeclsRecord &Visited,
-                               bool IncludeDependentBases = false) {
+                               bool IncludeDependentBases,
+                               bool LoadExternal) {
   if (!Ctx)
     return;
 
@@ -3513,11 +3514,12 @@ static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
     auto &Idents = S.Context.Idents;
 
     // Ensure all external identifiers are in the identifier table.
-    if (IdentifierInfoLookup *External = Idents.getExternalIdentifierLookup()) {
-      std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
-      for (StringRef Name = Iter->Next(); !Name.empty(); Name = Iter->Next())
-        Idents.get(Name);
-    }
+    if (LoadExternal)
+      if (IdentifierInfoLookup *External = Idents.getExternalIdentifierLookup()) {
+        std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
+        for (StringRef Name = Iter->Next(); !Name.empty(); Name = Iter->Next())
+          Idents.get(Name);
+      }
 
     // Walk all lookup results in the TU for each identifier.
     for (const auto &Ident : Idents) {
@@ -3540,7 +3542,8 @@ static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
     Result.getSema().ForceDeclarationOfImplicitMembers(Class);
 
   // Enumerate all of the results in this context.
-  for (DeclContextLookupResult R : Ctx->lookups()) {
+  for (DeclContextLookupResult R :
+       LoadExternal ? Ctx->lookups() : Ctx->noload_lookups()) {
     for (auto *D : R) {
       if (auto *ND = Result.getAcceptableDecl(D)) {
         Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
@@ -3557,7 +3560,7 @@ static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
         continue;
       LookupVisibleDecls(I->getNominatedNamespace(), Result,
                          QualifiedNameLookup, InBaseClass, Consumer, Visited,
-                         IncludeDependentBases);
+                         IncludeDependentBases, LoadExternal);
     }
   }
 
@@ -3614,7 +3617,7 @@ static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
       // Find results in this base class (and its bases).
       ShadowContextRAII Shadow(Visited);
       LookupVisibleDecls(RD, Result, QualifiedNameLookup, true, Consumer,
-                         Visited, IncludeDependentBases);
+                         Visited, IncludeDependentBases, LoadExternal);
     }
   }
 
@@ -3623,22 +3626,23 @@ static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
     // Traverse categories.
     for (auto *Cat : IFace->visible_categories()) {
       ShadowContextRAII Shadow(Visited);
-      LookupVisibleDecls(Cat, Result, QualifiedNameLookup, false,
-                         Consumer, Visited);
+      LookupVisibleDecls(Cat, Result, QualifiedNameLookup, false, Consumer,
+                         Visited, IncludeDependentBases, LoadExternal);
     }
 
     // Traverse protocols.
     for (auto *I : IFace->all_referenced_protocols()) {
       ShadowContextRAII Shadow(Visited);
       LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
-                         Visited);
+                         Visited, IncludeDependentBases, LoadExternal);
     }
 
     // Traverse the superclass.
     if (IFace->getSuperClass()) {
       ShadowContextRAII Shadow(Visited);
       LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup,
-                         true, Consumer, Visited);
+                         true, Consumer, Visited, IncludeDependentBases,
+                         LoadExternal);
     }
 
     // If there is an implementation, traverse it. We do this to find
@@ -3646,26 +3650,28 @@ static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
     if (IFace->getImplementation()) {
       ShadowContextRAII Shadow(Visited);
       LookupVisibleDecls(IFace->getImplementation(), Result,
-                         QualifiedNameLookup, InBaseClass, Consumer, Visited);
+                         QualifiedNameLookup, InBaseClass, Consumer, Visited,
+                         IncludeDependentBases, LoadExternal);
     }
   } else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) {
     for (auto *I : Protocol->protocols()) {
       ShadowContextRAII Shadow(Visited);
       LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
-                         Visited);
+                         Visited, IncludeDependentBases, LoadExternal);
     }
   } else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) {
     for (auto *I : Category->protocols()) {
       ShadowContextRAII Shadow(Visited);
       LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
-                         Visited);
+                         Visited, IncludeDependentBases, LoadExternal);
     }
 
     // If there is an implementation, traverse it.
     if (Category->getImplementation()) {
       ShadowContextRAII Shadow(Visited);
       LookupVisibleDecls(Category->getImplementation(), Result,
-                         QualifiedNameLookup, true, Consumer, Visited);
+                         QualifiedNameLookup, true, Consumer, Visited,
+                         IncludeDependentBases, LoadExternal);
     }
   }
 }
@@ -3673,7 +3679,8 @@ static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
 static void LookupVisibleDecls(Scope *S, LookupResult &Result,
                                UnqualUsingDirectiveSet &UDirs,
                                VisibleDeclConsumer &Consumer,
-                               VisibleDeclsRecord &Visited) {
+                               VisibleDeclsRecord &Visited,
+                               bool LoadExternal) {
   if (!S)
     return;
 
@@ -3712,7 +3719,8 @@ static void LookupVisibleDecls(Scope *S, LookupResult &Result,
                                   Result.getNameLoc(), Sema::LookupMemberName);
           if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) {
             LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false,
-                               /*InBaseClass=*/false, Consumer, Visited);
+                               /*InBaseClass=*/false, Consumer, Visited,
+                               /*IncludeDependentBases=*/false, LoadExternal);
           }
         }
 
@@ -3726,7 +3734,8 @@ static void LookupVisibleDecls(Scope *S, LookupResult &Result,
         continue;
 
       LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false,
-                         /*InBaseClass=*/false, Consumer, Visited);
+                         /*InBaseClass=*/false, Consumer, Visited,
+                         /*IncludeDependentBases=*/false, LoadExternal);
     }
   } else if (!S->getParent()) {
     // Look into the translation unit scope. We walk through the translation
@@ -3740,7 +3749,8 @@ static void LookupVisibleDecls(Scope *S, LookupResult &Result,
     // in DeclContexts unless we have to" optimization), we can eliminate this.
     Entity = Result.getSema().Context.getTranslationUnitDecl();
     LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false,
-                       /*InBaseClass=*/false, Consumer, Visited);
+                       /*InBaseClass=*/false, Consumer, Visited,
+                       /*IncludeDependentBases=*/false, LoadExternal);
   }
 
   if (Entity) {
@@ -3749,17 +3759,19 @@ static void LookupVisibleDecls(Scope *S, LookupResult &Result,
     for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(Entity))
       LookupVisibleDecls(const_cast<DeclContext *>(UUE.getNominatedNamespace()),
                          Result, /*QualifiedNameLookup=*/false,
-                         /*InBaseClass=*/false, Consumer, Visited);
+                         /*InBaseClass=*/false, Consumer, Visited,
+                         /*IncludeDependentBases=*/false, LoadExternal);
   }
 
   // Lookup names in the parent scope.
   ShadowContextRAII Shadow(Visited);
-  LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited);
+  LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited,
+                     LoadExternal);
 }
 
 void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind,
                               VisibleDeclConsumer &Consumer,
-                              bool IncludeGlobalScope) {
+                              bool IncludeGlobalScope, bool LoadExternal) {
   // Determine the set of using directives available during
   // unqualified name lookup.
   Scope *Initial = S;
@@ -3780,13 +3792,13 @@ void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind,
   if (!IncludeGlobalScope)
     Visited.visitedContext(Context.getTranslationUnitDecl());
   ShadowContextRAII Shadow(Visited);
-  ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited);
+  ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited, LoadExternal);
 }
 
 void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
                               VisibleDeclConsumer &Consumer,
                               bool IncludeGlobalScope,
-                              bool IncludeDependentBases) {
+                              bool IncludeDependentBases, bool LoadExternal) {
   LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
   Result.setAllowHidden(Consumer.includeHiddenDecls());
   VisibleDeclsRecord Visited;
@@ -3795,7 +3807,7 @@ void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
   ShadowContextRAII Shadow(Visited);
   ::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true,
                        /*InBaseClass=*/false, Consumer, Visited,
-                       IncludeDependentBases);
+                       IncludeDependentBases, LoadExternal);
 }
 
 /// LookupOrCreateLabel - Do a name lookup of a label with the specified name.